In The Simpsons's 1994 episode "Bart Gets an Elephant," Bart wins a radio call-in contest that has two prizes he can choose: $10,000 or a full-grown elephant. Being the force for chaos that he is, Bart chooses the elephant*. Hijinks ensue, finally ending with the elephant being moved to an animal sanctuary...where he immediately starts bullying the other animals.
A caretaker explains to Homer and Marge that, like humans, animals have personalities and some have had their personalities affected by abuse or other trauma, but adds that like some people, some animals are just jerks.
I tell myself that. Sometimes I have to.
* This despite Homer telling him "Bart, with $10,000 we'll be millionaires!"