Cars: [while watching "Raiders of the Lost Ark"] Some people call him "Dr. Jones" instead of Indiana Jones. Why do they do that?
Me: Indy is a professor at a university and went to school for a long time to get a degree called a doctorate so people can call him Dr. Jones instead of Mr. Jones.
Cars: Oh.
Me: You know your dad went to school for a really long time too and he can be called Dr. Pez instead of Mr. Pez.
Cars: I'm just going to call him Daddy.