"Please tuck it back in your diaper"

There are soo many things I never thought that I would have to tell my toddler. I say things that are just so random all day, and then I giggle to myself and have to remind myself that he is a boy and it is just going to get worse.

He is figuring out that he can play with his...ummm..."DD." His hand is down his diaper when he is watching tv...(think al bundy.) It really drives me insane, I do not know what to do about this. I don't want to make him think it isn't okay to touch down there, but I also want him to learn that he needs to do it when no one is around...! It's harmless though it really is, he is just a toddler. I have this weird fear that he is going to do it once he starts preschool though, omg I can just imagine that phone call home.

Today tops it though. He is sitting there watching Dora. I look over and he is sitting there with his legs like open...just watching tv. Then as I go back to reading on my laptop something caught my eye...yes his DD is hanging out the side of his Diaper. The next thing is what I never thought I would ever have to say "Can you please tuck your DD back in your diaper, it's hanging out the side." The funny part is, he looked down like "oh it is" and put it back. *bangs my head on the wall*

Is this a normal thing for little boys? I keep telling myself that it is, but I can only take so much. It can't be that fun to have hanging out? Can it? Oh goodness, and they say it gets worse when they are older, at least when they are older I hope I don't have to say "please tuck in your DD!" At least I would hope not!

I need advice moms of boys...I really do...what do I say to the boy? HELP!