I was sitting down in the floor to change Natalie's diaper and Noah slid the lid to one of his toys under my butt without me realizing it.  When I sat on it, he started laughing so I played along.  I said, "Hey - what's that?!"  It was all fun and games until he said:
"Isn't it funny to put the lid under something big and fat?!" and he started laughing with all his childhood innocence.
Yep - apparently he thinks my butt is big and fat and it's freakin' hilarious!!!