Me: (upon seeing something yucky on his arm) Gross, Jonah. What is that? Where did it come from.
Jonah: It is a booger. It came from my nose. I thought you knew where boogers came from?
Me: Yes, I know where boogers come from. I just didn't expect to see one on your arm.
Jonah: Well, I put it there. You don't like me wiping things on the kitchen table and making a mess.
True son, very true!