Some things to think about:
Gavin is currently in the nodding his head mode. Ask him if he's doing okay, and he'll nod.
Autumn thinks the word poopy is insanely funny. For example:
"What would you like for dinner Autumn?"
That kind of thing. So, it was a stroke of genius, in my opinion, to combine the two things. Thus, Autumn will turn to Gavin and ask:
"Do you like to eat poopy?"
And Gavin will nod his head. Hilarity ensues.
"Does mommy like to eat poopy?"
Nod. Laugh. Repeat.
"Does Lucy like to eat poopy?"
It's funny enough that anyone would laugh.