I (almost) wet my pants today for the first time. Devin wants a what?

So we are on the way home from the gym and Devin asked me out of the blue why he has hair on his legs. I told him that everyone has hair on their legs. Then I preceded to tell him that we all have hair on our arms, legs and heads. He said, " I know that mom." (very matter of factly) Then I told him when he gets older like a Daddy he will have hair on his face and chest too. He then said, "And I will have hair by my penis." I had to really hold back my laughter and be serious. I said, "Yes that is right you will." Devin then said, "I will also have a ginormous penis like Daddy does since I will be a big daddy." Again holding all my laughter back so I don't make him embarrassed or think he said something wrong. I said that he was right and that every part of him will get bigger as he grows up (naming his arms, legs, fingers etc). He told me he wants to have a ginormous penis but not any more hair. He said hair by his penis was yucky and hair on his face was scratchy. He said he just wants more hair on his arms and head so he can put gel in it and make it look like a shark. (we spike a mohawk into it sometimes when it is growing out and he thinks that looks like a shark)

I then let all the laughter out and he asked what I was laughing at and I told him that I like when he puts a shark in his hair. He agreed and wants to wear it like that tomorrow. I have not laughed like that in a long time. I love how natural and innocent their thinking is at this age. He is very intelligent and very observant and I really do look forward to teaching him all sorts of things.

We had a friend over today for a play date from his school. They were writing with chalk on the block wall out back. Devin asked him wanted to write each others names. His friend said he could not write and Devin asked why. Dev then said to his friend that he was older than him and he was already 4 and why can't he write? I just told him that maybe his friend knew how to do other things that Devin does not. Why do you say to that? The only reason Devin knows how to do it is because we work on it at home and it is reiterated at school.