Infant Sibling Jealousy

Nicole: [talking to her sons] Look, I understand — you're no longer the babies of the house, and that's a big adjustment. [...]But just because there's a new baby in the house doesn't mean I'll love you any less.
Gumball: So, you mean love multiplies?
Nicole: No, it divides. But I'll take the difference from your dad's portion and hope our marriage survives until you go to college.
Richard: Mm-hmm... wait, what?

— The Amazing World of Gumball, "The Rival"

In stories aimed at children in particular, it is a common plot for the child characters to dislike it when their parents have a new child. Reasons for this differ from being jealous of all the attention the new baby is getting, to being worried about falling into Middle Child Syndrome, or disliking how noisy and messy babies are.

Rarely however does this train of thought last past early childhood. The dynamic almost never becomes of the Cain and Abel sort once they're older, though Sibling Rivalry is common. The character might end up with shades of a Big Brother Bully but overall they are shown to love their sibling. There is frequently an aesop where the kid learns to love their sibling, or they simply grow out of it.

Compare to Dislikes the New Guy and Jealous Pet.

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Examples:

Advertising

• One car commercial features a little girl who likes having everything her way and to herself, such as her parent's car. She doesn't take it well to the news that she'll soon be an older sister.

Anime & Manga

• Fullmetal Alchemist: In a manga-only short, it's shown that Edward disliked Alphonse when they were infants. As a toddler, Ed thought their mother loved the baby more than him. It wasn't until his father told him otherwise that Ed became the very caring brother we know today.
• Kun in Mirai of the Future quickly notices how his parents are paying more attention to his newborn sister than him, complete with 4-year-old tantrums about it. By the end of the movie, he comes to terms with having Mirai in his life and develops a proper Big Brother Instinct.
• My Hero Academia plays with this for Shoto Todoroki's older brother Toya. He's the eldest of four siblings, so he was overall fine with his younger sister Fuyumi and younger brother Natsuo. It's when Shoto is born that Toya is at his most jealous—not because of Shoto being the newest child but because of what he represents to their father Enji (a kid with a perfect fusion of his parents' Quirks, and therefore a potential hero who he can train to take the #1 hero spot from All Might). In a moment of weakness, he outright tries to burn baby Shoto alive.
• Yaya from Shugo Chara! acts overly childish and expresses a desire to be a baby forever due to her jealousy over her new baby brother.
• Darkly and tragically played with in Fruits Basket with Machi Kuragi. Machi was pushed to the limit of her mother's extreme expectations so Machi would be chosen as an inheritor over her illegitimate half-brother. However, Mrs. Kuragi later had a baby boy and Machi was tossed aside while her mother made relentless comments about how "dull" Machi was. This is in spite of the fact Machi did nothing but try and make her mom happy. While Machi was never jealous or resentful of her brother, it didn't stop her parents from believing she was willing to kill her brother and threw her out of their home. All Machi tried to do was adjust her brother's blanket because she was worried about him being cold, but her mom thought Machi was trying to strangle him.

Comic Books

• Allergic: Maggie has this briefly when her mother says "sweetie" to her middle (the baby). Maggie indignantly says that she's sweetie.
• While Batman and Catwoman don’t have a child of their own (yet), Batman’s son Damian has been shown to be worried about it happening one day.
• Another Batman example, in the two-shot Year One: Batman/Scarecrow; Jonathan Crane, who in this continuity was taken from his teen mom's arms at birth and raised by his fanatically religious and abusive grandmother, tracks down his birth mother and discovers she married and had a baby girl...he takes it very well, as one would expect from someone with abandonment issues.

Comic Strips

• Baby Blues has older sister Zoe dismayed that her infant brother Hammie has taken away much of her face time with her parents. Wanda must be more careful with the infant, while Darryl no longer focuses solely on his "little princess," rather he marvels at having a son, a "chip off the ol' block." The antagonism eases once Wren is born.
• For Better or for Worse has young Michael learn to dislike his younger sister Elizabeth, who tends to be invasive and a crybaby. Not helping is that their mother Ellie tends to side with her in most disputes. Mike even has a nickname for Elizabeth: E. Lizard Breath. They grow out of it, especially when the newest rugrat April arrives.
• In Rerun's introductory story arc in Peanuts, Lucy is shocked to find out from her mother that another little brother has been born when she just kicked Linus out of their house. Linus isn't fond of Rerun at first, because Rerun will not stop crying when all he wants to do is read his book. Lucy tells Linus that she went through a similar experience with him when he was a baby, which inspires Linus to name their little brother Rerun. Lucy originally wondered why she couldn't just be an only child, but as time went on, exposure to Rerun began to affect her in a positive way.

Fan Works

• In the oneshot Her Max, Ruby initially didn't like having a sibling. She liked being the center of her parents' attention. Quickly, however, Ruby began to like taking care of Max and being a big sister.
• Initially, fifteen-year-old Ash doesn't like the idea of having a new half-sibling in Empty Nest. It isn't until Misty notes that he'll be able to teach his sibling about Pokémon that Ash starts liking the idea of being a big brother.
• The Code Geass oneshot Lesson One is about Cornelia telling a toddler-aged Lelouch how to be a good older sibling to his new sister Nunnally. Lelouch doesn't like Nunnally because he's afraid she'll get all the attention.
• Twelve-year-old Dick Grayson doesn't take graciously the apparition of toddler Damian into his and Bruce's life into In For a Penny, eagerly waiting for Bruce to send the baby back to his mother. He ultimately confesses his fear that Bruce will stop caring about him with his "true", biological son at home.
• In the fourth books of the Dusk to Dawn series, Damian reacts unfavourably to the news that his stepmother Selina is pregnant, and admits while high on weed-laced cake that he's afraid the unborn baby is a threat to his station as Batman's heir and his parents' affection. He's still sulking in Teen Titans: Call of Blood, the first book of the spin-off, and treats his teenaged younger sister from the future with hostility. By the epilogue where his sister Helena is born, however, Damian loves her instantly and is a devoted big brother going forward.
• Destiny (Afterandalasia): Lady ran away from home because her parents were having a baby and she was worried that her parents wouldn't love her anymore. Lady trusted the wrong man and was killed by him.
• ER: In a series of Doug & Carol stories, the couple adopts a baby shortly before Carol discovers she's pregnant again. From the moment the baby is born, the adopted daughter is extremely jealous of him, to the point where the nursery door is kept locked so that she won't try to harm him and 15 years later, not only still resents him for usurping her position as the youngest, but is equally displeased to hear that her parents are expecting again.

Film — Animation

• In The Boss Baby, Tim is envious of the attention his baby brother receives, and suspicious when the infant acts odd around him. Tim soon finds out that Boss Baby is on a mission to discover why babies are losing their market share of love, and originally agrees to help him for the sole purpose of wanting him out of his life. Over the course of the movie, Tim and Boss Baby bond with each other, and by the end, when they finally achieve their goals, they realize how much they miss each other and agree to officially become brothers.
• Dingo Pictures: In an infamous scene from Dinosaur Adventure (that was the origin of the "Yee" meme), Tio finds out that he has a new brother and is worried that his parents don't want him anymore. His friend Peek teases him about it.
  Peek: Mom and dad have a new baby, now you are nothing for them.
  Oro: Yee ("Peek!" in the original version). How can you say something like that, the majority of us have brothers and sisters, the parents love all their children in the same way.
• A large part of the plot of the first Franklin movie, Franklin and the Green Knight, is Franklin worrying that he'll become The Unfavorite when his new baby sister is born. This worry is only increased when everyone fawns over the upcoming baby during a baby shower. Later, this fear is soothed when he meets an armadillo with a baby brother who tells him that his parents have enough love for both him and his brother. Franklin's friend Snail has a similar fear - he worries that Franklin won't have any time for him once the baby is born. Oh, and Franklin's worries being soothed turns out to be reasonable, as there is no evidence in the fifth and sixth seasons of the show (both of which feature a version of Franklin's new sister, Harriet, that is able to talk and walk), that either child is treated as a favorite.
• In The Rugrats Movie, Tommy doesn't get along with his newborn brother Dil at first. He hates how much noise Dil makes and feels his parents are neglecting him to focus on his brother. Tommy and his friends trying to send Dil back to the hospital is how they end up lost in a forest. By the end of the film, Tommy realizes how much he loves Dil and his Big Brother Instinct often appears in later episodes of the TV series. This is possibly the only example of this trope where the older sibling is a baby too, only a year older than the newborn.

Film — Live-Action

• In Addams Family Values, Wednesday and Pugsley believe that, in the Addams Family, when a new child is born, one of the old children has to die, which simply isn't true (well, not anymore). Despite this, they spend a lot of time seemingly trying to murder their new baby brother. Then again, this being the Addams family, that may just be how they show affection.
• Blue Bayou: Antonio's young stepdaughter Jessie by his pregnant wife Kathy adores him and worries that he will love his biological daughter more than he loves her. Antonio makes it very clear that he loves her as much as one can love their child.
• Dear Zindagi: Kaira was envious of her new baby brother because her mother arrived with him and spent all her time with him after abandoning her for years at her grandparents'.
• The Little Rascals episode "Bouncing Babies" has Wheezer get a baby sister that cries and fusses too much. Wheezer's friend Farina suggests taking the infant to the hospital and trade it in for a goat, which is precisely what Wheezer does. After learning an important Aesop, Wheezer undoes the exchange.
• In Look Who's Talking Too, Mikey quickly becomes frustrated with his new baby sister Julie and bickers with her throughout the movie, blaming her for their parents' marital problems and destroying her favorite toy. He later regrets this and starts to bond with her.
• Zig-zagged in Stuart Little. Stuart's brother is happy that his parents are adopting a kid, however he is upset when his new sibling turns out to be an anthropomorphic mouse. He takes some time to warm up to Stuart.

Literature

• The Angelina Ballerina book Angelina's Baby Sister shows Angelina going through this when her little sister Polly is born. She's upset that everyone is paying more attention to the baby than her and doesn't love her anymore. She throws a tantrum and breaks a prize she won; her mother then comes and assures her that she is just as loved and Polly just needs more attention because she's a baby.
• In The Berenstain Bears and Baby Makes Five, Honey Bear is born, and Mama, Papa, and their relatives spend all of their time with her, making Sister feel largely ignored (Brother is an exception, which is lampshaded by the narrator mentioning that he went through something similar when Sister was born, so he's used to the arrival of an infant and doesn't worry about it). Sister also becomes bad-tempered, to the point of attacking her dolls because they remind her of babies and, when given a school assignment to draw a family picture, deliberately omits Honey. The Bear family then shows Sister home movies of when she was a baby, which makes her realize that she used to be just like Honey. This causes Sister to change her attitude towards Honey, symbolized by her drawing a new family picture that includes her.
• The Baby-Sitters Club:
  • Jamie Newton has this toward his infant sister Lucy in early books (especially Claudia and Mean Janine) but he gets over it. A lot of it is revealed to stem from knowing that his mother wants an older sitter on hand to take care of the baby, while he wants his beloved Kristy and Claudia, who have watched him practically his whole life. Once it's clear that the BSC is still going to be babysitting him, Jamie feels a lot better and is cool with being a big brother (though his jealousy does occasionally come back in later books, which is understandable - he's only four, after all).
  • In Kristy and the Mother's Day Surprise, this is Andrew's reaction after learning that their parents are adopting a two-year-old girl. He gets better after Kristy comforts him.
  • There's a brief moment where Andrew's older sister Karen is worried that her baby sister will become Watson's Daddy's Girl instead of her. This is gone into more in-depth in the "Little Sister" spin-off series - an entire book is dedicated to Karen's complicated feelings about Emily Michelle, seemingly feeling somewhat like Emily is replacing her as her father's little girl (particularly since she now only lives with him a few days a month due to the divorce arrangement between her parents, while Emily lives with him all the time). She gets better about it, and is shown to be a pretty good big sister to Emily in later books.
  • In the Little Sister series it's also mentioned at one point that Karen was quite jealous of Andrew when he was first born.
  • Jenny Prezzioso's jealousy over the upcoming baby is the main subplot of Mary Anne Vs. Logan, thinking the baby will get all her parents' attention. Once she sees her baby sister, she comes to love her, though her jealousy occasionally comes back in later books. (It doesn't help that her mother turns into a Pageant Mom for baby Andrea.)
  • In Dawn's Book, Dawn remembers feeling left out when Jeff was born.
• I'm Not a Baby! is a book based on Bobby's World. In this book, Bobby becomes jealous of the attention that his new twin baby brothers, Jake and Al are receiving from his parents, Howard and Martha, so he demands to be treated like a baby as well. He soon discovers the disadvantages of being treated like a baby; he is too big to fit in a high chair or the twins' bathtub, he finds wearing underpants better than being put back in diapers, he finds his own toys more fun to play with than the twins', and he doesn't like being put down for a nap when he could play instead.
• Melody from Dolphin Song has two half-siblings, Lisa and Justin, both below age three. Melody adjusted easily enough when Lisa was born, but ever since Justin came along, Melody has felt like her father John and her stepmother Felicity are more interested in the kids than they are in her. She also dislikes the mess and chaos of living with two small children.
• In the second book of the Fudge series Superfudge, both Peter and Fudge go through this in varying degrees with regards to their new little sister Tootsie. Peter is initially worried that the baby will be a repeat of Fudge and ineffectually threatens to run away from home when he finds out about the pregnancy, but he comes around quickly after seeing Tootsie for the first time. Fudge meanwhile is jealous of the fact that he's no longer The Baby of the Bunch, especially since this is around the time their parents start taking his bad behavior more seriously.
• Enid Blyton likes to use this trope sometimes:
  • Sally in the Malory Towers series is so jealous of her baby sister in the first book that she won't even look at her, and then denies any existence of the baby.
  • Robert in the The Naughtiest Girl series has two little brothers that he was so jealous of when they were babies, that he started bullying younger children, pretending they were his brothers. Five years on, he's still doing it and only stops when his jealousy is realized.
• A dark take on this trope occurs in It. Patrick, one of the bullies in Henry's gang, smothered his infant brother to death because he hated that he was getting more attention than him.
• In Julius, the Baby of the World by Kevin Henkes, Lily was originally thrilled to be a big sister when her Mom was pregnant with her baby brother, Julius. Following Julius' birth, she took on a more hostile personality towards him. She did not like having to share her bedroom with him and hoped her parents would send him away. She even tried scaring him, making him disappear, and pretending he didn't exist, all of which sent her to the uncooperative chair. When Lily's parents throw a party in Julius' honor, Lily's cousin Garland acts the same way towards Julius that Lily did, which causes Lily to change her attitude towards Julius for good and defend him.
• Averted in Junie B. Jones. When the titular character is told by her mother that she will be having a baby boy, she is overjoyed. She also thinks about being bossy towards him. When he's born, she actually mistakes him as a monkey and brags about him to her friends.
• Played with in My Next Life as a Villainess: All Routes Lead to Doom!, given that the younger sibling is adopted and there's only a few months between them. The original Katarina from the game was incredibly jealous of Keith stealing away their father's attention and would verbally abuse him well into their teenage years (something that leads to her death in at least one of the routes). The new much kinder Katarina (having the Past-Life Memories of a Japanese schoolgirl who played the game and always wanted a younger sibling) defies this and tries to be his Cool Big Sis almost immediately after meeting him.
• In Ramona Forever, when Mrs. Quimby becomes pregnant, Ramona struggles with the thought of losing her status as the youngest and becoming the middle child. When her new sister is born, she feels even more left out when she's not allowed to visit her in the hospital. A friendly doctor diagnoses her with "siblingitis" and "prescribes" some extra attention as the cure, which her father duly gives her. The following book Ramona's World, reveals that she still feels jealous now and then when baby Roberta gets more attention than she does, but for the most part she can accept it and is a caring, protective big sister.
• In Red Sky In The Morning: In a family of three children, seven-year-old Katie is extremely jealous of the attention lavished on her baby brother Ben, who is born disabled, and whose birth has prevented them from going on holiday. Her older sister Anna talks sense into her, using (in her own words) awful sarcasm.
  Anna: I suppose you think we should put Ben into a horrid home, with cruel nurses, while we go off and have a good time?
• Roys Bedoys: Downplayed in “Meet the Baby, Roys Bedoys!”, where part of Roys’s reason for finding the newborn Joys annoying is because Mrs. Bedoys is spending more time with her than with him, but mostly, he’s just annoyed because she sleeps a lot and isn’t toilet trained.
• A Series of Unfortunate Events: It's mentioned off-hand that Klaus disliked Sunny at first. He grew to like her within 6 weeks of her birth.
• In A Baby Sister for Herry, a Sesame Street book, Herry dislikes his new baby sister, Flossie, at first. He dislikes whenever his parents have to stop playing with him to take care of her and having to play quietly whenever she tries to sleep. He tries acting like a baby himself to get their attention. When Herry's mother shows him pictures of him when he used to be a baby, this gets him to realize that he used to be just like Flossie. This gets Herry to change his attitude towards Flossie and help take care of her.
• Sherlock Holmes: In "The Sussex Vampire", Holmes investigates claims of a man's wife sucking the blood from her own newborn's neck. The real culprit was the man's first son Jack, who hated his stepbrother for the attention it was taking away from him, and for not being deformed like he was. The mother was sucking out the poison from the blowgun darts Jack had used to try to murder the baby.
• In the book Stupid Baby, the bunny Simon gets a brother who he thinks is stupid.
• In Thumper's Little Sisters, a book based on Bambi, Thumper does not get along with his three younger sisters at first, feeling that their parents love them but not him. Although Bambi assures him that his parents will never stop loving him, and that they will have more time for him when his younger sisters get older, things unfortunately get worse for Thumper. His father tells him not to thump in the burrow when his sisters are sleeping, and his mother tells him not to eat all the dry grass in the burrow, so as to save some for his sisters. When his sisters get older, they get on his nerves by asking him questions and wanting to play with him. When Thumper saves his sisters from a hungry-looking dog by leading it to his burrow, his parents scold him for this, telling them that now they will have to move because the dog knows where they live. Upon hearing this, Thumper runs away and gets caught in a trap, but is soon rescued by his sisters and his friends. Thumper is grateful, and after his sisters tell their parents about how he saved them from the dog, they are proud of him for being a good big brother. It's at this point that Thumper realizes his parents will always love him no matter how many younger siblings he may have.

Live-Action TV

• Subverted on Bones. Booth and Brennan think this is happening when Parker is found to be not listening to the sitter and a toy car he built with Booth is found broken along with some family photos. But in the end, Parker reveals he was building Christine a mobile of family photos and a badge from Brennan’s lab coat.
• Buffy the Vampire Slayer: Buffy has this to Dawn, who ironically resents her in turn.
  Buffy: She gets to be a kid, and she acts like it's the biggest burden in the world. Sometimes I would like to just curl up in Mom's lap and not worry about the fate of the world. I'd like to be the one who's protected, who's waited on—
  [Twisted Echo Cut to Dawn]
  Dawn: —hand and foot, getting her own way. Always the favorite.
• Charmed (1998): Toddler Wyatt winds up getting so jealous of baby Chris that he keeps using magic to steal his stuff, and eventually orbs him somewhere outside the house, where he's thankfully found by grandpa Victor. Grams casts a spell that is supposed to end their sibling rivalry, but it backfires by making the sisters act like immature children instead.
• In an episode of Frasier, the now-adult brothers Frasier and Niles are having a fight, at which point the younger, Niles, has a flashback to Frasier trying to strangle him to death as an infant in his crib. Frasier himself apparently simultaneously has the same flashback, as he screams "You stole my mommy!!"
• The Fresh Prince of Bel-Air: This is Ashley's subplot in the episode where the family thinks about how the new baby will impact their lives. She has a fantasy about the family ignoring her and forgetting her name, as she will no longer be The Baby of the Bunch.
• Good Luck Charlie: Charlie constantly asked that her baby brother Toby be left somewhere, thrown away, or ignored him as much as she could get away with. Gabe felt the same way about her, and each older sibling of the Duncan household felt the same way about their immediate younger sibling.
• Little House on the Prairie: In the two-part episode The Lord is My Shepherd, Laura is jealous of her baby brother Charles Jr. and refuses to pray for him when he falls ill. But when the baby dies, she's guilt-ridden and runs away to ask God to send him back and take her instead.
• The Golden Girls:
  • In the episode "Clifton Avenue Memoirs," Dorothy and Sophia go to visit their old apartment in Brooklyn. Via flashback, Dorothy thinks about when Sophia and Sal brought their new baby Phil home from the hospital; she deliberately breaks a plate out of both jealousy and a desire to get her parents' attention. Sal gives her a pep talk and assures her that even though their family is changing, they'll always love her, too.
  • In "Ebbtide's Revenge," Dorothy reminisces about the day Phil was brought home, saying that while she was at first angry at him for "stealing" her parents' love, she later realized that he instead brought them all closer together and made them feel "more like a family." Sadly, this reminiscing is happening in her eulogy for Phil, who recently died.
• Once Upon a Time uses this in an interesting way in season 4's "The Snow Queen.” Emma struggles with abandonment issues after a childhood in the foster care system, and although she finds her family and resolves some of them, her Supernaturally Young Parents having another child is unexpectedly difficult. Emma is an adult, so the feelings aren’t directed at the baby, but more at the situation and watching her parents parent her brother. However, since Emma is experiencing some Power Incontinence, these feelings come out subconsciously through her powers, and the reactions from her parents only make her feel more rejected—such as when Emma hears Snow being called a “first time mother” and finds she’s making the baby’s bottle boil, prompting Snow to be hesitant to hand over Neal. The Snow Queen, season 4A’s Big Bad and one of Emma’s former foster placements, preys on this insecurity to convince Emma to join her. This makes Emma’s Power Incontinence worse, and after accidentally injuring her father, she runs off to isolate herself.
  The Snow Queen: I don't have to know you, Emma. I've been you... different, misunderstood, alone. And now they've chosen to have a new child. And don't you think that they thank their lucky stars every day that he was born normal?
  Emma: They love me.
  The Snow Queen: You can't love somebody you don't understand. And do you know what happens when people don't understand something? They learn to fear it. And then they look at it like a monster!
  Emma: Shut up! (blows a hole through the brick wall of the police precinct)

Music

• In "Lonely Boy" by Andrew Gold, the lonely boy gets a baby sister when he's two.
  Well, he ran down the hall and he cried,
  Oh, how could his parents have lied?
  When they said he was an only son,
  He thought he was the only one.

Video Games

• In The Sims 4, while it is possible for them to be happy about it, there are also two potential negative moodlets that children and teens can get from meeting a new sibling. There's a sad "New Sibling..." moodlet and an angry "Unwanted Sibling" moodlet. When infants were added to the game, it became possible for toddlers to get a negative sentiment which causes them to feel sad or angry when their parents pay attention to their younger sibling.

Puppet Shows

• Sesame Street:
  • A variant in Episode 1230 (part of Season 10); S.A.M. the Robot is jealous of Moe, his baby brother who is a small electric motor. S.A.M. resents the attention that Moe receives for doing nothing of value, until David and Olivia help S.A.M. understand his role as a big brother and Moe's potential. S.A.M. pictures Moe becoming something important someday, such as an airplane motor or a generator for a building.
  • In the Direct to Video release, "A New Baby in My House", when Snuffy gets mad at Alice for breaking his toy tiger, Mrs. Snuffleupagus tells them a story called "Prince Firstly's Little Surprise", which is also about a boy who gets mad at his younger sister. When Princess Azealia is born, Firstly becomes frustrated because of all the attention she recieves. He first tries acting like a baby himself to get his parents to pay attention to him, then he tries acting naughty, but is caught and told off by Lord Elmo. He eventually decides to run away, but is soon found by Queen Quinella, who explains to him that she'll always love both him and Azealia equally. Firstly then changes his attitude and helps her and King Goodheart take care of Azealia.
  • In the 3-part episode, "Three Bears and a New Baby", Baby Bear has mixed feelings about his baby sister, Curly. While he is excited about being a big brother, and gives Curly her name, he worries that their fairy tale, The Three Bears, will never be the same again. Baby Bear's first night with Curly doesn't go over too well, due to how much attention their parents give her, and this also interferes with his bedtime routine. Papa Bear tells Baby Bear that he will always love both him and Curly equally, and will find a way to have time for them both.
• In the Wimzie's House episode, "Babies Have It Made", Wimzie is jealous of her baby brother, Bo, because he doesn't get scolded for his actions due to not knowing any better, and their parents and grandmother have to do everything for him. This makes Wimzie wish that she were a baby herself during her naptime. Wimzie then has a dream that makes her experience what it's like to be a baby, and she finds out it isn't as fun as she thought it would be, due to her friends and family not understanding her, and having to eat baby food instead of pizza. When she awakens from her dream, she realizes the advantages of being a five-year-old kid and changes her attitude towards Bo, even going as far as defending him when Jonas objects to her hugging him.
• In the The Wubbulous World of Dr. Seuss episode, "Lester Leaps In", Sarah Hall-Small becomes jealous of her new little brother, Paul, because of how much time her parents spend with him, and how they hardly pay attention to her anymore. Whenever they do, it's usually to remind her to be considerate of him, such as not playing her big bass thumper bumper too loud when he's trying to sleep. Sarah eventually gets the idea of acting like a baby herself to get her parents' attention, until her parents tell her that they'll always love both her and Paul equally. Upon hearing this, Sarah changes her attitude about Paul and promises him that she'll be the best big sister ever.

Web Animation

• GoAnimate: A common type of video is "X calls the Baby Stupid", wherein when a new baby is born or brought home, the older sibling (sometimes an original character, sometimes a character from a show aimed at kids the user really doesn't like) will call the baby stupid. This will cause the baby to cry, and the parents will ground the older sibling for a ridiculously long time, causing them to run away crying. They will then calm the baby down and tell them their older sibling can't bother them anymore.

Webcomics

• Age Of Bronze: Deiphobus really does not like that Paris is revealed to be his long-lost brother, especially after he'd beaten all the royal children (himself included) at the games. That Paris continues to gain honor and glory (and the most beautiful woman in the world), further cementing his place as second in line to the throne (after Hector) doesn't help at all.
• Yet Another Fantasygamer Comic: When it's revealed the baron's son Lucas and the blacksmith's (half-orc) son Glon were Switched at Birth, Lucas does not take it well at all, even if Lucas eventually succeeds the baron and Glon stays in the Black Mountain. Both eventually get much better, and become true Bash Brothers in time.

Western Animation

• The Amazing World of Gumball: Inverted and invoked in "The Rival", the Whole Episode Flashback to Anais's birth: Gumball and Darwin were looking forward to their new baby sister, but she turns out to be a murderous Brainy Baby who sees them as competition for their parent's affection. Nicole still ends up giving her sons the usual spiel about not loving them less with the new baby, but only because Anais framed them for bullying her.
• Arthur: In "D.W.'s Baby", D.W., who was at first thrilled to have a new baby sister, quickly grew tired of having Kate around the house, due to her constant crying at night and stinky diapers. She tried to get Kate in trouble by blaming her for things she or somebody else did, and tried to sell her at a Garage Sale for 50 cents. When she runs away to Grandma Thora's house, Thora reminds D.W. that when Kate grows up, she'll have a mom, dad, and brother, but no sister to take care of her. This quickly convinces D.W. to go back to her house and be the best big sister ever to Kate.
• Big Mouth: When Jessi learns her dad is having a baby with his new girlfriend, she's immediately distraught because it means her mom and dad are definitely not getting back together. She imagines the new baby as a horrifying cheese monster that takes over her life. While she mostly gets over this for the rest of Caitlyn's pregnancy, her fears crop up again when her sister Delilah is born and she overhears her dad saying he isn't going to make the same "mistakes" he did raising Jessi. She imagines Delilah speaking telepathically to her, threatening to take all the love for herself. Jessi only learns to get along with Delilah when a "Freaky Friday" Flip puts her in the baby's body and she realizes how hard it is to communicate your needs as a baby.
• Bobby's World: In "Big Brother Blues", Bobby is upset that everyone in his family is too obsessed with the new baby's pending birth to pay attention to him, to the point that he considers running away from home. But when his mom finally gives birth to the twins, he quickly warms up to them and can't wait to be their Big Brother Mentor.
• Caillou: In one episode, Caillou is not happy to see that his new sister, Rosie, is getting more attention from the family than him. This infamously leads Caillou to pinch Rosie at some point in the episode (which is arguably nicer than what he did in the book, where he bit her).
• Dinosaur Train: In "Tank's Baby Brother", Tank the Triceratops gets a new baby brother, Tuck. Tank dislikes all the attention Tuck gets from his friends and family and feels largely ignored. Buddy and Tiny soon realize how upset Tank feels and decide to play with him to cheer him up. When Tuck says his first word, "Tank", Tank quickly warms up to him.
• Family Guy: Played for laughs in the episode "Yug Ylimaf", where after Stewie and Brian go back in time to the day Stewie was brought home from the hospital. The family is fawning over him while Peter is lying on the couch, pounding his fists and crying, "I wanna be the baby!"
• Jem: Flashbacks show that Jerrica and Kimber disliked their foster sisters Shana and Aja when they met as children. They, however, became best friends within a year and by the time they're adults, they're in a band together. The series treats them more like friends than sisters, though the comic reboot makes it clear that they're sisters.
• Kaeloo: When Mr. Cat was born, both of his older brothers quickly developed a hatred towards him for supposedly being their mother's favorite and would bully him as a result. Unlike most examples of the trope, the brothers continued to hate and abuse him for years until Mr. Cat got sick of the abuse and decided to run away from home entirely.
• Kim Possible: In "Big Bother", Ron's parents adopt a little girl called Hana. Ron is not happy, though at least part of this is because his parents were absurdly sudden about it, only being told once Hana took his room. He gets over it after Monkey Fist attacks her, and adores her for the rest of the series.
• A version with dogs happens in the Martha Speaks episode "Martha Plays Favorites" Martha is jealous of the attention the family's new puppy Skits is getting, so she does things like take Helen's socks and pee on the rug intentionally.
• My Little Pony 'n Friends: In "The Prince and the Ponies", the baby ponies, who over the second season have started to grow up, are deeply resentful of the two pairs of newborn twins, whom they find annoying and troublesome and who demand constant attention from the older ponies.
• A brief flashback in the Pepper Ann episode "Cat Scan" shows a young Pepper Ann was jealous of baby Moose and even tried to get rid of her by putting her in the mailbox. Their mother solves this problem by getting her Steve the cat.
• Rugrats (1991): In "Angelica's Worst Nightmare", Angelica freaks out at the news that her mother is pregnant, to the point where she has nightmares about having a baby brother who steals all her stuff, turns into a giant, and eats her. Most of it stems from the fact that Angelica is used to being treated like a princess, and that she doesn't like having to share anything, especially her parents' love. Subverted, however, when it turns out that her mother had false pregnancy symptoms.
• The Simpsons: "Lisa's First Word" shows Bart was unhappy with Lisa's birth, especially with Homer fawning over her because it coincided with a run of good fortune. Though a good part of Bart's misery came from random events indirectly caused by Lisa (e.g. Lisa gets Bart's old bed, so Homer makes Bart a new one with a Monster Clown carved into the headboard). He was about ready to leave home until hearing Lisa's first word was "Bart".
• South Park: Kenny McCormick becomes jealous when his parents reveal in "Cartman Joins NAMBLA" that they are planning on having another child and he takes steps to ensure his mother doesn't get pregnant. She does anyway, but the ending reveals that the baby is another Kenny, meaning that he was jealous of himself. While this is initially played as a joke, it would be foreshadowing for Kenny's Born-Again Immortality much further down the line.

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