Is crazy hereditary?

Dix: Do you want some of this chocolate bunny? I can cut it into chunks.
Mom o'Dix: What part is that? Did it come from his ear?
Dix: Yes.
Mom o'Dix: It might be wax. (eats chocolate) I'm glad you gave me the ear instead of the butt. Mmmmm, that's good.
Dix: This is his foot.
Mom o'Dix: Oh boy, toe jelly.