Clashing Cousins

Cousins having a tense relationship is not unheard of. Often times this is the product of a Sibling Rivalry between their parents rubbing onto the children. Other times this has similar reasons to a Sibling Rivalry considering how close many cousins are (usually closer than other parts of the extended family). Or maybe they just don't like each other and their familial relationship cannot fix that. Either way, the cousins don't get along much of the time.

Compare to Sibling Rivalry and in extreme cases Cain and Abel. Can often overlap with (or lead to) Feuding Families. Kissing Cousins is the complete polar opposite of this trope.

---

Examples:

Anime & Manga

• In the source material of Cardcaptor Sakura, Chiharu and Yamazaki have the Puppy Love version of Belligerent Sexual Tension, with Chiharu often acting violent whenever he enraged her. In the Nelvana dub the two were retooled into cousins, turning their dynamic into rivalrous cousins instead.
• Food Wars!: The Nakiri cousins Erina and Alice were very close to each other until Alice departed to North Europe to learn more about cooking. Due to Erina's father Azami educating his daughter into an iron-hearted Supreme Chef who should look down on any dish that is considered terrible by their standards and him throwing every letter away that Alice sent to Erina, the cousins have barely contact each other until they are reunited in Tootsuki. Due to these circumstances, they developed a rivalry, with Alice trying to overthrow Erina's position as the best student of their year, while Erina is "trying"^note she's not doing that much to accomplish this to defend her position. After Azami's return to Tootsuki, Alice is trying to get his Erina from his hands and to protect her, reconciling their cousin relationship.
• Chapter 98 of Kaguya-sama: Love Is War reveals that this is the case with Kaguya Shinomiya and Maki Shijo, with the latter being the only character in the series who is outright rude to Kaguya, such as mockingly calling her "Auntie" despite the two being the same age. Flashbacks in chapter 168 show that this was actually invoked by the latter's father, as the two sides of the family have been hostile to one another for decades, though that same chapter has the two of them put aside their differences and and bond over a porn DVD.
• The hotheaded cousins, Ginta and Tsutomu of Marmalade Boy have frequently had childish bouts with each other since they were little, with their mutual rivalry towards Yuu over the girls that they like, Miki and Arimi respectively, being the one thing they can agree on. Once Ginta moves on from Miki and he and Arimi begin to develop feelings for each other, Tsutomu calls him out for it and it causes their own rivalry to peak, resulting in a brutal fight once Ginta finally reaches his limit with him. The two do reconcile a few minutes after the fight and Tsutomu decides get over Arimi to fully support his cousin's relationship going as far as to help bring the two back together after the couple have a falling out later in the series.
• Naruto: During the Chuunin Exams arc, it's revealed that Neji despises his cousin Hinata for being the eldest daughter (and thusly the heiress apparent) of the Main house of the Hyuga Clan. While his own father was the twin brother of her father, the current head of the Hyuga, clan politics led to Hizashi being shunted into the Branch family, where they were effectively enslaved by their own kin. Neji resents Hinata for being born into a far better position than he was; despite being recognized as a natural prodigy while Hinata is seen as weak and too timid, she's still viewed as his superior simply due to who her father is. Neji gradually defrosts after Naruto defeats him in the Tournament arc, and he and Hinata gradually grow closer, culminating in Neji sacrificing himself to protect his cousin during the Fourth Shinobi War.
• Downplayed in One Piece with Zoro and Kuina who had a Friendly Rivalry before the latter's death and were paternal second cousins (though both of them were completely unaware that they were related).

Comic Books

• This trope often happens to Donald in Disney Mouse and Duck Comics, most often with lucky jerkass Gladstone Gander and bothersome beatnik Fethry Duck. In Gladstone's case, it's compounded by also being a romantic rival to Donald for Daisy's affections. Donald is a lot closer to Fethry because he's not nearly as obnoxious as Gladstone, often going on adventures with him willingly, although they do bicker a lot.
• X-Men: The longstanding enmity between "Black Tom" and Sean "Banshee" Cassidy is not diminished by their being cousins and having grown up together.

Fan Works

• Child of the Storm has the canonical cousinly relationship between Harry and Dudley. Unfortunately, as Word of God notes, here Dudley never has his canonical experience with the Dementors to show him how awful a person he was and inspire him to become a better person (especially regarding Harry, who in canon saved him). Instead, he ended up in the Foster System after his parents were arrested, and fell right into the lap of Sinister. Turns out he has an X-Gene too, and he reappears as the Blob a.k.a. the Beast of the Red Room and a Grade-A monster, and thinks he can do what he wishes with Harry, whose powers are restricted. As it turns out, not so much. Then, he gets turned into a vampire and makes the grave mistake of almost killing someone Harry likes a great deal. The results are brutal, precise, and terminal.
• Everything Changes (Milkyway Scribbles) depicts Ash and Gary as cousins. The two are rivals due to their similar ages and personalities. They clash a lot and Gary often bullies Ash.
• In A Game of Castles, Bowser and the Koopalings are cousins, but Bowser doesn't get along well with them. Sometimes it's normal family teasing, but others (like Ludwig) are genuinely out for his throne.
• Johanna Mason: They Will Never See Me Cry: Seneca mentions that the District 9 tributes during the 54th Hunger Games were cousins whose mutual hostility resulted in a Mutual Kill.
• Ned and Tony Stark in A Man of Iron. Ned dislikes Tony for his flippant attitude, arrogant and narcissistic personality, and utter disregard for his Northern heritage, while Tony dislikes Ned for his Honor Before Reason attitude, grim personality, and seeming refusal to move from the past. The trope gets eventually downplayed as the two of them get past their differences and learn to understand and appreciate the other better.
• The Night Unfurls: Downplayed for Alicia and Prim. They are cousins on good terms, and both of them care for each other's well-being, but their opposing views on Kyril (the former mistrusts him while the latter vouches for him) causes tension between them.
• Skyhold Academy Yearbook: In Bright Jewels, Chained City, feuding cousins Gaston and Celeste are both vying for the same important political appointment. (They're based on cousins Grand Duke Gaspard and Empress Celene from Dragon Age: Inquisition.)
• Mei Terumi and Kurotsuchi in Son of the Sannin are both descendants of the same clan, but since Mei's mother defected from Iwa to marry a man from Kiri, Kurotsuchi views Mei as the daughter of a traitor. The latter's personality does not help in smoothing things over, either.

Films — Animation

• Annabelle from All Dogs Go to Heaven is an angel who has an evil cousin named Belladonna. Belladonna is implied to be a Fallen Angel.
• Downplayed in the How to Train Your Dragon films, as it's not explicitly stated that Hiccup and Snotlout are cousins (this is mentioned in the books). Snotlout is a bully and implied to be at least slightly resentful of Hiccup's position as the chief's son, although as Hiccup becomes more popular with the other kids, the resentment eases up and they clash much less.
• This is implied in The Lion King II: Simba's Pride. Nuka and Vitani are two lions raised in the Outlands after being banished from the Pridelands as young cubs. Their parentage is never confirmed, but it's implied that they're Scar's children (thus making them Simba's cousins and Kiara's first cousins once removed). Kovu is explicitly adopted by Scar (and possibly by Zira as well). The Outlanders are enemies of the Pridelanders until undergoing a group-wide Heel–Face Turn near the end.
• Arrow and Rudolph from Rudolph the Red-Nosed Reindeer (1998) are enemies and cousins (as shown by throwaway lines showing that their fathers are brothers). Arrow is The Bully who teases Rudolph for his unusual nose. They're also pining after the same doe — Zoey.

Films — Live-Action

• The main antagonist of Black Panther is T'Challa's previously unknown cousin Erik.
• The Favourite: Sarah and Abigail are cousins and this is why Sarah helps Abigail get settled at the palace in the first place. Once Abigail starts ingratiating herself to the Queen a bit too much for Sarah's liking, their relationship turns completely antagonistic as they compete for the Queen's favor.
• Kissin' Cousins: Second lieutenant Josh Morgan is given a mission to convince some distant relatives living in Tennessee to lease their land to the army. He gets along well with those relatives except for cousin Jodie, who is very hostile to him until the end.
• Scream 4 devolves into this in the third act, after it's revealed that Jill Roberts is Ghostface, and has been reenacting the Woodsboro murders but stages herself as the Final Girl to gain fame, following in the footsteps of her cousin Sidney Prescott. Naturally, Sidney calls her insane.
• Stuart Saves His Family: The Smalleys do not get along with Cousin Ray and his family, such as burying one of their own family members in Aunt Paula's cemetery plot.
  Jodie: You know, my aunt Paula paid for that plot!
  Ray: With money she could have used to help my family after my father fell off the roof!
  Mrs. Smalley: I made a ham for your father!
  Ray: That was not a quality ham!
• Wolves: The Wills brothers and Cayden are second cousins and Cayden and Larson trade some ugly words over Cayden threatening to instigate a turf war and Larson being unwilling to fight the mountain werewolves. More notably, Wild Joe Wills initially seems like a mentor to Cayden, but they fight to the death after Cayden learns Joe killed Cayden’s adopted parents.

Literature

• The Accursed Kings: Due to starring the antics of the French and English royal families of the 13th century, this is inevitable. Made even more confusing that nearly everyone can truthfully refer to many other characters as "my cousin" due to the complicated parentage.
  • Villain Protagonist Robert d'Artois starts by arranging for The Reveal of his hated cousins' infidelity to their husbands, the princes of France. He doesn't so much hate his cousins as he does hate their mother Mahaut d'Artois, his paternal aunt.
  • After the male line of Phillip IV goes extinct, the throne goes to his nephew Philippe de Valois (the son of the king's brother). His cousin Isabelle de France (daughter of the late king) contests this, wanting the throne of France to go to her son Edward III of England.
  • Robert keeps backing his cousin by marriage Philippe de Valois which pays off once Philippe takes the throne... but then a scandal turns up involving falsified documents where Robert's guilt is proven, leading Robert to flee France and join the English side of the Hundred Years War.
• The Dark Artifices: Cameron Ashdown is a Dogged Nice Guy who is pro-Downworlder. This brings him into conflict with his cousin, Vanessa, a Jerkass member of the Cohort, a virulent anti-Downworlder faction within the Clave.
• In the Deryni works, Conall Haldane is jealous of his cousin Kelson. Kelson is the son of King Brion Haldane, while Conall is the eldest son of Brion's younger brother Nigel. Kelson is sometimes low-key about his authority, while Conall is very (perhaps excessively) proud of his royal rank; Conall haughtily stands on ceremony at the court of the Earl of Transha, and Kelson scolds him for it. Later on, Conall secretly seeks to learn to use the "Haldane powers", though they're traditionally reserved for the ruling monarch (who is, at that point, Kelson), and he pursues Rothana Nur Hallaj after Kelson disappears in The Quest for Saint Camber in large part because she's not only beautiful but also because he once witnessed Kelson wooing her. Conall actually persuades her to marry him since Kelson is presumed dead and his father Nigel is then in a coma and not expected to come out of it. Eventually, Kelson and Conall fight a duel arcane at the end of The Quest.
• Earth's Children: Ayla and Broud are technically adopted cousins, though they never refer to each other as such, and both view the other as their Archenemy. Broud develops an Irrational Hatred of Ayla for unintentionally overshadowing his transition into adulthood and not fitting in easily; Ayla hates him for being arrogant and entitled, not seeing why she should have to be at his beck and call simply because he's the future leader, which further inflames his resentment. Broud physically and psychologically bullies Ayla for years, and eventually begins sexually abusing her; it's made clear he isn't doing it out of lust as he finds her ugly, but because he enjoys dominating and hurting her. He gives up when she stops fighting him and doesn't outwardly let it bother her. He eventually has her cursed with death for arbitrary reasons (which he'd wanted to do for years), though she manages to humiliate him and declares that he can never make her die.
• The Forsyte Saga: Young Jolyon is a rebellious artist with a liberal political mindset, who loves to defy the rules of the high society and the traditions of the Forsyte family. But his cousin Soames is an uptight solicitor with a conservative political mindset, who believes that being rich and respectable is the key to both success and happiness. Of course, things become even worse between them after Soames's wife starts an affair with Jolyon. But they didn't like each other before that happened either.
• Inverted in Fudge-a-Mania, when Peter and his rival Sheila become (step)cousins due to his grandmother marrying her grandfather.
• Harry Potter:
  • Harry was reluctantly taken in by his aunt Petunia's family as a baby after his parents died. They spoiled their son Dudley, who used Harry as his favorite punching bag. After Harry saves Dudley from a Dementor attack, Dudley starts becoming a less repugnant human being, actually showing concern for Harry's safety before they part, and later sending Harry some of his childhood items after Petunia dies. Word of God says that as adults, they sometimes get their children together for playdates.
  • In Order of the Phoenix, it is established that this was the dynamic that Sirius Black had with his cousins Bellatrix Lestrange and Narcissa Malfoy. Ultimately, the former kills him in the climax of that book.
  • Played With for Nymphadora Tonks and Draco Malfoy, who are first cousins^note Draco's aforementioned mother, Narcissa Malfoy, was the sister of Tonks's mother Andromeda and fight on different sides of the Wizarding War (The Order for Tonks, the Death Eaters (at least, initially) for Draco). However, the two are never shown interacting face to face, let alone fighting each other. In fact, Tonks makes an offhand remark about Draco, calling him "the Malfoy family".
• The titular protagonist of Horrid Henry and his cousin Steve loathe each other's company, to the point of Henry scaring Steve out of his bedroom in order to get out of sleeping in his aunt's attic. This forms a tit-for-tat war between them whenever they meet at family reunions.
• Secret Vampire: James and Ash are maternal cousins and don't get along. Ash is everything that James pretends to be: a cold, calculating womanizer who views humans as playthings. Ash in turn views James as a pathetic bore for his sympathy for humans and disapproval of his troublemaking. When James realizes Ash has tricked Poppy into leaving town with him and likely has malicious intentions, he's prepared to kill Ash if he brings his soulmate to harm.
• Warrior Cats: While their kinship was never discussed, cousins Mudclaw and Onewhisker turned into enemies in a fight for succession. It was rather one-sided on Mudclaw's part, as he was furious about having his deputyship revoked in favor of Onewhisker just seconds before Tallstar died, making Onewhisker the WindClan leader over him. This led to Mudclaw and several other warriors among three Clans rebelling and trying to kill Onewhisker before he could officially become the leader.

Live-Action TV

• Taken to the logical extreme in Alma Gêmea: Cristina and Luna aren't just clashing, they're mortal enemies. Initially, the hatred is one-sided on Cristina's part: she is very jealous of Luna for marrying Rafael, the love of her life, and for receiving the family jewels instead of her (who is the oldest cousin), making her feel like The Un-Favourite. Cristina is indirectly responsible for Luna's death, as she is killed by Guto, who Cristina sent to rob the jewels. After Luna reincarnates as Serena, not only does Cristina's hatred for her cousin rekindle, but their conflict is no longer one-sided, and it gets progressively worse throughout the story, with Cristina trying to get Serena killed multiple times. She also still bears a huge grudge against Luna, whom she blames for Rafael having no desire for her, prompting her to attack Luna's atelier several times, madly yelling at the dead woman.
• Belgravia: John Bellasis doesn't know that Charles Pope is his cousin (Charles is the son of John's deceased first cousin Edmund), but sets himself up as a rival because John's aunt Lady Brockenhurst is funding Charles' business. Charles is also in love with John's intended Lady Maria Grey, but doesn't think he can win (to be fair John would be happy to release Maria but her mother presses the matter). Things escalate when John learns that Charles is Edmund's legitimate son with Sophia Trenchard, leading to John attempting to murder Charles.
• Cinderella and the Four Knights: The reason the Kang cousins draw so much intrigue is that they are never seen in the same room together due to their contrasting personalities. Ji-woon and Hyun-min are the most antagonistic; their establishing character moments in the first episode involve getting into a spat about their shared heritage, and they're in a love quadrangle with the main female characters Ha-won and Hye-ji.
• Downton Abbey: Mary and Matthew are distant cousins and do not like each other when they first meet, as Matthew is poised to inherit Mary's family home and fortune (which Mary sees as her right) while Matthew is attracted to Mary but thinks that she's a snob. They eventually warm to each other considerably, but circumstances prevent them from acting on their feelings. Also, Matthew's mother Isobel doesn't get along with Mary's mother Cora or grandmother Violet at first, though they also mellow out as the series progresses. In the first two seasons, the main Crawley branch calls Matthew and Isobel "Cousin Matthew/Isobel" and vice versa, but the two Crawley branches drop this as they become closer.
• In How to Be Indie, Indie's Sitcom Arch-Nemesis is her 'evil cousin' Rubi, who is constantly one-upping her.
• On Justified Boyd and Johnny Crowder are cousins in a family of criminals. They are initially on very good terms, but then Boyd's Heel–Faith Turn results in Johnny being crippled and Johnny grows to hate Boyd. They seem to reconcile for a while but Johnny was simply waiting for a good opportunity to backstab Boyd. The cousins become bitter rivals and much blood is spilled before Johnny is killed.
• The premise of the CBBC comedy Kevin's Cousins: Kevin's horrified that his cousins (who happen to be girls) will be staying with him for the summer.
• Love Alarm: Jo-jo has a terrible relationship with her cousin Gul-mi, who blames Jo-jo for all of her family's problems since Jo-jo has been raised by Gul-mi's mother ever since she became an orphan. It only gets worse when Jo-jo begins a relationship with Sun-oh, who Gul-mi has a crush on.
• In Part I of Obi-Wan Kenobi, Princess Leia's cousin mocks her for being adopted and thus not a real Organa. Leia fires back by accusing him of simply parroting his father's words for his approval without knowing what they really mean.
• The Outpost: Despite the blood relationship with his cousin Yobhan, they really don't like each other. Most of it is down to how to handle humans, with Yobhan believing in a strong, firm, and hard treatment of humans with Zed being a bit more merciful.
• Supernatural: Sam and Dean Winchester are the perfect, pre-destined blend of one elite hunting family line and one family line of world-class scholars of the supernatural. However, in the Supernatural world, hunters and Men of Letters don't get along and despite their last name, their hunter genes actually come from their mother's side, the Campbells. When the Campbell clan resurfaces in season 6 (mostly, second and third cousins of Sam and Dean), they have a deep disdain for both brothers. This ultimately leads to bloodshed, although this may be primarily because the season 6 Campbells are almost all demon-possessed. However, it is shown in season 4 flashback episodes that Samuel Campbell never approved of Mary and John's marriage (Sam and Dean's parents) because John wasn't from a hunting family. Also when Henry Winchester appears in a season 8 episode, he's appalled to find out that his grandsons are hunters instead of scholarly Men of Letters.
• That's So Raven: In a first season episode called "Dissin' Cousins," Raven is revealed to have a rich and beautiful (but also mean and snobby) cousin named Andrea who lives in Europe and gets to travel to all kinds of exotic places all over the world—Raven's friend Eddie also has this huge crush on Andrea. In the end, Raven and Andrea manage to patch things up when their relationship turns out to be a case of Mutual Envy—Andrea explains to Raven that even though she has the chance to live in Europe and travel to all kinds of exotic places, she hates having to move around so much and has always been secretly envious of Raven's much more "normal" life (it's unknown if Andrea knows about Raven's Psychic Powers).

Professional Wrestling

• After his Face–Heel Turn, Roman Reigns, with his special counsel, Paul Heyman, became WWE Universal Champion. His first opponent turned out to be his cousin, Jey Uso. After beating him nearly to unconsciousness, Roman wanted Jey to acknowledge him as the head of the Samoan Dynasty. After their rematch, which Roman won, Jey had a choice to either "fall in line," or be excommunicated from the family. Jey fell in line, and brother Jimmy would follow a few months after. After putting up with Roman's disrespect and abuse for three years, the Usos finally superkicked Roman, and Jey pinned Roman Reigns at Money in the Bank. Something that hasn’t happened since December 2019.
• The Rock clashed with Rikishi after The Reveal of the infamous "Who ran over "Stone Cold" Steve Austin" storyline.

Toys

• SuperThings: Witchy Way's cousin is Walpurgis, first introduced in the webseries. Both are powerful witches on opposing factions: Witchy Way is a heroine, while Walpurgis is a villainess.

Video Games

• Crusader Kings 2: As patrilinear cousins are closely enough related to inherit a claim on each other's titles, this is a common sight. Furthermore, if they are in each other's line of succession, they will gain a casus belli to take their cousin's titles, meaning that they will often try to dethrone one another.
• Dragon Age has a few examples.
  • In Dragon Age II, the Exiled Prince DLC brings this into existence for the city-state of Starkhaven, which is ruled by the Vael family. It's eventually revealed that a friend of the ruling Prince and Princess had them, as well as their children and grandchildren (with one exception), murdered by thugs; she then propped up their idiot nephew as the new Prince, all so that she could marry him to her own daughter and become more powerful. The lone exception to the slaughter was youngest son Sebastian, a priest, who recruits Player Character Hawke to help him get to the bottom of things and eventually take what is now his throne back from his cousin.
  • Empress Celene and Grand Duke Gaspard in Dragon Age: Inquisition ended up this way after Celene essentially stole the Orlesian throne from him via political maneuvering. Eventually Gaspard gets fed up with his cousin's very different way of handling things and it erupts into civil war. Lampshaded by an illegitimate nobleman who remarks that when he quarrels with his cousin, some wine gets spilled and maybe someone loses a tooth. When the empress quarrels with her cousin, the country gets torn apart and thousands of people die.
• In Fire Emblem Echoes: Shadows of Valentia, Alm fights against his cousin Berkut on several occasions. However, neither party is aware of their familial relationship until the final act. Once Berkut realizes that Alm is the son of Berkut's uncle Emperor Rudolf, and the true heir to the throne of Rigel, Berkut goes off the deep end.
• In Pokémon Gold and Silver, Clair, the eighth and strongest gym leader, has a one-sided rivalry with her cousin Lance, the game's Champion. Since Second Place Is for Losers, she refuses to give up trying to beat him, though off the battlefield they've got a pretty good relationship.
• Zigzagged with Marie and Callie from Splatoon. In their personal lives, they have a close, sisterly bond filled with lighthearted teasing (maybe that's why Squid Sisters is their stage name). In the first game, though, they're always on rival teams due to being the hosts of Inkopolis News. It's usually all in good fun, but during the Christmas 2015 Splatfest, Callie goes off-script and calls out Marie for her rude and sarcastic behavior, stunning her into silence.
  Marie: I'm PLENTY nice, you know! I care about-
  Callie: Yourself? Winning? Insulting me on live TV?

Visual Novels

• Lily Satou and Shizune Hakamichi from Katawa Shoujo are revealed in both of their arcs to be cousins. They get along poorly due to their contrasting personalities. It doesn't help that they can't communicate well due to Shizune being deaf and Lily being blind. Despite this, they reconcile on Lilly's route, and in Shizune's route, Shizune admits that she was in the wrong in their disputes.
• In Phoenix Wright: Ace Attorney – Trials and Tribulations, it is revealed that Mia's Arch-Enemy Dahlia Hawthorne is actually her cousin. While Dahlia's mother Morgan despises Mia's mother Misty(Morgan's younger sister) for becoming heir to the Fey Clan in her stead, Dahlia doesn't care at all about Morgan's grudge against her sister, and instead hates Mia for getting her convicted of murder.
• In Umineko: When They Cry this is downplayed between the four Ushiromiya cousins, who mostly get along with each other and don't carry the rivalries and resentments their parents do, but George admits to being jealous of Battler in the past and sported an Entitled to Have You attitude towards women when he realized Battler was getting more attention from the maid Shannon at the Ushiromiya estate. By the time of the main story he's outgrown this and is deeply ashamed that he once acted this way.

Web Animation

• Animated Inanimate Battle has Nabla and Alef, two math symbols who are also cousins and don't get along very well. Alef finds his cousin's detailed plans to be boring and finds simpler ways to execute during challenges (and since he has most of their team, Team 4, under his influence, they tend to go with Alef's method). He also gives an encyclopedia with every page torn out of it except for the pages about donkeys for Nabla's birthday. That's not saying Nabla is completely helpless, though, as she managed to become friends with Glue due to both of them hating Alef, and she might be able to turn the tides of control over her team with her help.

Web Comics

• In Dean & Nala + Vinny, Vinny hates having to spend any time with his obnoxious cousin Marcello, as the latter teased him throughout their entire childhood. To make matters worse, Vinny's mom is completely oblivious to her nephew's antics, so Vinny just has to grind his teeth and take it when they are together.
• In Drowtales there are several examples among the noble family since drow tend to have Massive Numbered Siblings and encourage competition:
  • Nega'fanea Val'Illhar'dro and her cousin Balsii eventually end up going to war over the leadership of the clan, since while Balsii is the regional ruler of the clan's home city of Nuqrah'shareh she's wildly xenophobic and believes Nega, who was born in a neighboring city of Val'Ravern, is weak and leading the clan down a path of destruction. Balsii goes so far as to try and stage a coup during a civil disturbance in the city but is thwarted when the leaders of the two other most powerful clans in the city refuse to support her.
  • Among the ruling Vel'Sharen clan the clearest example is between Chrys'tel and her cousin Nihi'liir, clearest on this page and with the latter confirmed by Word of God to be a deliberate Shadow Archetype of the former. In their case, it's clearly an extension of their mothers.
• Girl Genius:
  • The underhanded Tarvek Sturmvoraus and his brutish cousin Martellus von Blitzengaard are both potential heirs to the Lightning Throne and Martellus makes numerous assassination attempts on his cousin and instigates several battles between their allies.
  • It's revealed that Agatha has a cousin on her mother's side in the form of Zola, who was also employed by a conspiracy to claim Agatha's title. She refers to killing Agatha as "prun[ing] the family tree".
  • Tarvek is also the victim of constant abuse from his cousin Violetta, who spent years thinking he'd gotten her reassigned to Mechanicsburg in an attempt to upend her carer. Even after learning that he did it to save her life, she still finds him incredibly annoying. Violetta also detests Martellus for what he's done to Agatha and spends time undermining his plans.
• In the opening arc of Katamari, the King of All Cosmos recruits Ace to act as the Dashing Prince's "backup" in case he needs help dealing with the UFO. Ace, however, cares more about getting in Prince's way and humiliating him than dealing with the cow-loving aliens, even when they abduct Daisy, one of their second cousins. Ace accuses Prince of being a Glory Hound who keeps Stealing the Credit for everyone's hard work; however, it swiftly becomes clear that this is nothing more than Psychological Projection on his end, as Ace is the self-absorbed Attention Whore. He's also just a straight-up bully who gets a laugh out of things like giving the Prince an empty box for Christmas and claiming it "symbolizes their friendship".

Web Videos

• Cousins James and Percival Darkmagic in Acquisitions Incorporated form a bitter rivalry, though it's mostly one-sided, as Jim is too self-obsessed to remember anyone having beef with him. The rivalry stems mostly from the fact that Jim has always been their grandfather's favorite grandson, and Percy, The Unfavorite. Subverted later when we learn that the two are secretly brothers, turning their relationship into Sibling Rivalry instead.

Western Animation

• In the The Adventures of Jimmy Neutron, Boy Genius episode aptly titled "Clash of the Cousins", Jimmy has an antagonistic relationship with his cousin Eddie, who is trying to destroy the Neutron family in order to get their money for himself.
• Ben 10: Ben and Gwen have an antagonistic relationship and are always trading insults. Unless one of them is in trouble, in which case the other one will do whatever it takes to help.
• Clash and Video from Jem have gotten poorly all their lives. They were next-door neighbors growing up as well. Their relationship seems to be an extension of the Sibling Rivalry between their fathers.
• The Delightful Children from Down The Lane in Codename: Kids Next Door are villains and Numbuh 1's adopted cousins, though the latter point is never actually discussed in-series. (It's only very late in the series that it's revealed that their fathers are brothers.)
• In The Crumpets, Caprice enjoys bullying her adopted cousin Cordless, even though she usually respects him in "Acne Dents Happen". Despite protecting him from her harassing family due to his radioactive powers in this episode, she tries to treat him by leaving him inside a refrigerator. In other episodes, she fooled him into dropping his video game portable, injected him with a huge syringe by surprise, and pushed him out a window to his adoptive mother's car. In one phone call between the cousins, Caprice hears that he will get revenge.
• Superman and Supergirl in DC Super Hero Girls are cousins as in most versions, and while they're not enemies, Supergirl feels some resentment due to constantly being compared to him and expected to be like him.
• Elena of Avalor,
  • Early on, Chancellor Esteban seems like an antagonist in the making towards his cousin Princess Elena, and everyone just puts up with his jerkassery because he's family and is a vital figure in keeping the kingdom running. It eventually turns out that this only goes as far as Jerk with a Heart of Gold; he deeply cares about his family, and if anything, his relationship with Elena is more Like Brother and Sister. Thanks to Character Development, he goes from deliberately trying to undermine Elena (whom he sees as irresponsible) to trusting her judgement. However, we find out that he helped Shuriki take over Avalor which led to Elena's parents getting killed by the sorceress, and as far as he knew, Elena seemingly getting killed too. Esteban did this because he felt like an outcast and wasn't listened to, but he didn't want any of his family to be hurt and regretted this moment since. After getting them back, Esteban wanted to do everything he can to make sure he doesn't lose Elena or any of his remaining family but still refused to come clean with his secret. And then after Elena finds this out and doesn't believe Esteban has changed when he explains himself, she actively attempts to hurt Esteban for it, resulting in Esteban going back to wanting to take over Avalor.
  • Elena is eventually revealed to have another cousin, Cristobal, who is seemingly much more friendly and good-natured than Esteban. Unfortunately, this is an act. Not only had he also collaborated with Shuriki during her coup and subsequent reign of Avalor, he doesn't show any hint of regret that Elena's parents were killed (though he also didn't have involvement in that part, whereas Esteban indirectly did), and when Shuriki returns, he resumes working with her in hopes that she will overthrow Elena.
• G.I. Joe: Renegades: Roadblock with his cousin Heavy Duty, the educated White Sheep of their lower-class family. To complicate matters, Roadblock is on the lam framed for a crime he didn't commit and Heavy Duty is sent to capture him. The two reconcile after going through a Chained Heat situation and visit their grandmother together at the end of the episode.
• Lilo & Stitch: The Series has Stitch going around fighting and befriending his "cousins" (though being created by the same person makes them closer to siblings). In particular, Experiment 625 remained Stitch's enemy until he underwent a Heel–Face Turn in the finale.
• In Mixels, royal cousins Camillot and Mixadel are pitted against each other, primarily one-sided, thanks to Mixadel disapproving of Camillot taking to the "common Mixels" so fast.
• In My Little Pony: Friendship Is Magic, Babs Seed is a bully to her cousin Apple Bloom. However, Babs later has a Heel–Face Turn and the two become friends.
• In Phineas and Ferb, Ferb has several cousins from England who are convinced that living in America has made him less British. This prompts a competitive game of soccer/football between the boys, along with their friends.
• In Ready Jet Go!, Jet's cousin Zerk likes to annoy him and compete with him. Not to mention that Zerk constantly makes speciesist remarks towards Jet's human friends. They seem to get along better in Season 2.
• In Rugrats (1991), one-year-old Tommy Pickles has an antagonistic relationship with his three-year-old cousin, Angelica, who regularly calls him and his friends "dumb babies" and bosses them around. Even ten years later in All Grown Up!, they still don't like each other very much.
• Taz-Mania: In "Just Be Cuz", Francis X. Bushlad has a one-sided rivalry with Edgar, his brainy younger cousin who is much more successful at capturing wild animals than him. As Francis' goal in the series is to capture Taz so that he can pass his manhood ritual and take his father's place as Chief of the Mudpeople, he at one point uses Edgar as bait to capture Taz. However, his shoulder angel convinces him to reconsider, saying that if he lets Taz eat Edgar, he'll be just as bad as him.

Real Life

• Often Truth in Television throughout European history. European royal houses frequently married into each other for political purposes. By the 19th century, nearly all European royals were related in some way. When many countries ultimately went to war, cousins would often be on opposing sides. World War One is likely the penultimate example, where all the main great powers monarchs (Tsar Nicholas II of the Russian Empire, Kaiser Wilhelm II of the German Reich, King George V of the British Empire, and Emperor Franz Joseph I of Austria-Hungary) were all cousins. In a sad irony, the close relationships had all resulted from marriages that Queen Victoria advocated, precisely to cause closer ties by the countries she hoped would prevent a war, but sadly it did not. Nicholas and Wilhelm were even friends, with the former begging the latter not to make war, but this didn't work. The strong family resemblance among them was even noted at the time.

---