My boys do love their penises. Hayden holds it at all times when he is naked, as if it is attached to a rudder and he is steering himself around the house with it. Logan recently discovered his- what a glorious bath that was! It was a little disturbing how proficient he was with it. Innate. He hasn't bothered with it much lately, instead focusing on carrying toys around in his mouth like a puppy with its ball. We've been calling him Fido.
I do go around naked in front of them, but feel a bit self-conscious with Hayden. He is very interested in body parts these days, randomly asking and taking inventory. Recently he came up to me while I was naked, pointed to my crotch and said "dat yo penis?" I told him no, I don't have a penis. "Mommy, you don't have penis?! Why?" Mommies don't have penises because we are girls. A glance over at Fillip showed him intensely (intentionally) unaware of what was going on, no help at all in my awkward situation.
Recently, while friends were over for dinner, Hayden looked across and asked me "Mommy, you have boobies?" Yes Sweetie, I have boobies. This led to pointing out everyone's boobies, then determining who had penises.
At dinner with Fillip's Grandmother the next night at a restaurant, Hayden loudly confirmed "Mommy, you don't have penis?" No, no I don't have a penis.
A look at Fillip, and he was doubled over laughing, no help at all.