In Brave, Merida earlier complained about how her mother never listened to her and that she thinks she knows best. But when the "Woodcarver'' tries to dissuade Merida from getting a spell to "change her fate", she doesn't listen even when the "Woodcarver" outright says that many people tend to be disappointed by the spell. Apple doesn't fall far from the tree, hmm? Also, Elinor complained to Fergus that Merida is stubborn and prideful and must have gotten it from him to which Fergus laughed and pointed out how Elinor herself had plenty of stubbornness and pride.
Character dialogue in How to Train Your Dragon shows that Hiccup and Stoick are this: They are both stubborn, prone to coming up with crazy ideas, and have a tendency not to listen to the advice of others.
ParaNorman: Agatha's "curse" was to inflict this on the people who had her put to death, so that they could see what she went through. It also has a heroic example, where Norman points out that he and Agatha are the same.
In A Bug's Life, when Princess Atta talks to Flik about how she feels like everyone in the colony has their eyes on her, Flik finishes her sentence "Like they're waiting for you to screw up."
Tiger:I can tell we have an awful lot in common / Even though we look as different as can be!
Jack Frost and Pitch Black aka the Bogey Man in Rise of the Guardians, where the latter even mentions how dark and cold go together well. Both want to be believed in by children but unlike Pitch, Jack doesn't want to be feared or hurt anyone.
This example is notable in that most cases of Not So Different are really just the villain's last-ditch attempt at getting under the hero's skin, often used when he or she has exhausted all other options and is on the ropes. Pitch was pretty much winning at this point in the film, and all signs indicate to his subsequent We Can Rule Together moment being genuine. It also takes on a whole deeper meaning if you're aware of Pitch's origins in the books the film is based off of: Pitch is a Fallen Hero in the books, and only became evil when the monsters he was tasked with guarding tricked him into thinking that his daughter was imprisoned with them. He freed them, hoping to save her, and then was transformed into Pitch Black the Nightmare King. In Jack's case, his origin is similar, but has a happy ending. You find out right before the Final Battle that Jack was originally a young man living in colonial America, who'd gone ice skating with his younger sister when the ice had started to crack. He sacrificed himself to save her, so the Man in the Moon resurrected him as Jack Frost.
In the sequel to The Little Mermaid, Ariel forbids her daughter Melody from going into the sea, very much like how her father didn't want her to go to the surface when she was a mermaid (though in this case, Ariel had a more valid reason).
Po from Kung Fu Panda has a lot in common with the Big Bads of both films. In both cases, the main difference is that Po is able to grasp the Aesop of the film while the Big Bad can't or won't despite Po's efforts to help him.