Along with being naked, he's very interested in all of his newly uncovered body parts! So he will take any opportunity to drop "penis" into a conversation. Like the other day when we were driving, and a little voice popped up from the back seat:
D: Yes, buddy?
M: Penis, Daddy!
D: Um... ok.
We recently spent some time with my friend Michelle and her two beautiful children. I was trying to be a good parent and friend by preparing Matthew ahead of time that her older daughter, Parker, has peanut allergies. So I said to Matthew, "no peanuts around Parker!" and he said "no penis Parker!" Who knows... maybe he was just pointing out the obvious that Parker is a girl ;).
I'd say more, but my nudist baby is standing on the coffee table with a black Sharpie in his hand, so I better take action before anything is marked permanently!