I have two kids in diapers. One who needs help after using the toilet. And the rest of them think scatological humor is the best.
My two year old, who is still in diapers, has decided that when she's sleepy and feeling belligerent, it is good to go around insulting people by saying, "You poop in your diaper!" Thanks to her siblings, she's also learned lovely phrases such as "Poo-poo head."
My older, classically-educated children, have been thoroughly enjoying their Latin class. Especially when they learned that boy was puer. Or as the girls like to say, "Puer. It's like poo-air. Therefore our brother is really flatulence."
I suppose that's what I get for keeping a copy of Everybody Poops in the house.