From the first teaser trailer, we see how close Drac is with Dennis, his grandson.
Upon seeing him for the first time, Dracula promises no harm will ever come to Dennis as long as he lives, is very sweet.
Dennis in general was adorable.
Winnie and Dennis' moments are a literal case of Puppy Love. She often calls Dennis her Zing.
When Drac saves Dennis from falling to his death.
Also doubles as a Funny Moment, but Drac's friends being worried over little Dennis was also quite sweet and tells that they care about him a lot.
Many moments during Johnny and Mavis' wedding at the beginning of the film, including Dracula and Mavis dancing on the ceiling and Dracula watching Mavis walk down the aisle. For a split second in Drac's eyes, Mavis is shown to be a kid again, ala Dracula's little girl getting married.
In an extremely subtle touch, while all the other wedding guests' eyes are showing their feels over Johnny kissing his bride, the mummy's light-spark "eyes" tremble just a tiny bit. The way Murray's eyes are depicted makes normal facial expressiveness difficult, but that little quaver says it all.
Drac's updated song for Mavis, apart from being funny — this is as much concession as Drac's giving — is incredibly sweet.
And you'll always be my moonlight
But now on wings of love you soar
Now that you're Johnny's girl, Johnny's girl
And kind of Daddy's, too
Your mom would be so happy 'cause she always knew
Love is making room for all the best in you.
Winnie is heart-meltingly cute.
Dracula and Mavis' playful chase is an adorable father and daughter moment, made even better when Mavis reveals her pregnancy.
Mavis singing Dennis Twinkle Little Star, then Dracula singing his version. Mavis sings with him and eventually falls asleep with Dennis in her arms. Drac soon joins them.
The relationship between Johnny and Mavis. The past few years have made the two closer than ever and they often call each other by terms of endearment like 'hon' or 'honey'.
The way Johnny looks so proud of Mavis when she showed off her awesome biking skills. Especially since earlier he said he'd had years to get as 'good' as he was, yet he didn't show a hint of jealousy or threat to his manliness when Mavis did so with far greater ease.
Johnny: You see that? That's my girlfriend, suckers! Mavis: (teasingly) Your wife, Johnny. Johnny: My wife! Even better!
When Dennis's cousins ask him who his favourite monster is, Dennis replies with the fictional kids show monster Cakey. It's precious that Dennis doesn't even see the vampires and mummies and werewolves and other monsters that surround him at all times 'as' monsters. To him they're his friends and family.
During the "monster-masquerade" party, Dennis is playing pretend in his Batman costume. If you pay attention to what he says, he repeats lines that he and his grandfather has said earlier in the movie, even devolving into Dracula's accent. This is basically him equating his grandfather to his favorite superhero.
Winnie comforting Dennis when he feels his family is disappointed in him for not being a vampire. She lets him know instantly that she doesn't see him any different. It may be a simple little girl crush or a true Zing, but that little werewolf put a warm little glow in Dennis's heart.
Despite Dennis having absolutely no powers, when Bela first appears he does what he can to shield and protect Winnie. He really does care about her.
Mavis and Drac's reactions when they see Dennis in bat form for the first time. Mavis looks shocked at first, then smiles with pride, and the look of unbridled joy on Drac's face is just precious.
Dennis' vampire powers awakening when Bela brutally hurts Winnie.
In the aftermath of the battle, Dennis asks Drac if him being a vampire makes him cool now. Drac, however, happily assures him that he was always cool, regardless of his species. Ultimately, it didn't matter to Drac on whether or not his grandson had any monster abilities—he loves him the way he is.
Johnny telling Mavis how great she is and how he'd be so proud if Dennis grew up to be just like her. She so touched that she tells him that she loves him.
During the scene where Drac stands up to Vlad, it is clear he realizes his mistake in trying to change Dennis to bring out his inner vampire, saying that if Vlad can't accept him for being half human than he's the one who is the fool. Mavis, who had been angry with Drac for what he did is moved by this as she realizes how overprotective she has been. Giving him a hug.
Mavis: Oh daddy!
Vlad overcoming a lifetime of prejudice to stop Bela from staking Johnny, and then warns the creature to stay away from his family and him.
Griffin getting an actual girlfriend at the end.
A subtle one. At Johnny and Mavis's wedding, we see one of Johnny's brothers (groomsmen) and a female monster (bridesmaid) looking rather freaked out at being next to one another. Come the climax, when Bela's forces attack, one of them corners the female monster. Johnny's brother intervenes and attempts to defend her, but gets injured. But what does she do when Bela's goon attempts to hurt him? She grabs the brother by one of her tentacles to protect him and uses two others to hold down and beat up the goon...all the while kissing the brother for his act.
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