Bodily Functions

Why is it, when having a conversation with a child, the conversation inevitably turns south, and we find ourselves discussing poop or pee? Oh, you can try to change the subject, but once the topic is out there, the needle is stuck in the groove! Every answer after that is going to involve bodily functions, and they're going to laugh and laugh because they're a kid, and that's funny to kids. On Saturday, I was sitting, eating a donut with a friend of mine's son. He's a well behaved 3 year old, and I guess I was asking for it. I asked if he liked mustard on his donut. Of course his answer was a resounding NO! But this was an open invitation to the grossology exhibit. I then asked him if he liked ice cream. He shook his head yes, but when I asked him about ketchup on his ice cream, he turned his nose up. I don't know how the conversation, at this point, twisted, but one of the next topics that came up, was my butt. Uh oh, here we go. So after a couple of exchanges, I just got up from the table. I know it's rude, but a 3 year old doesn't take offense due to their attention span. Well, yesterday afternoon, I was talking to a friend and a relative of mine, and the topic came up of a mutual friend who is on a diet. Now this is the most bizarre diet I've ever heard of. It involves the urine from pregnant women to suppress the appetite. (I warned you). Next thing you know, we are three grown men cracking jokes about urine! Playing tricks on our friend with some Mountain Dew, walk out of the bathroom with a jar in our hand, freezing our waste product and putting in popsickle  sticks, etc., etc. After our friend bashing party, I left thinking, "I'm such a three year old". My conversations STILL spiral downward, satirizing bodily functions! Why is that so funny? I could just say the word "poop" completely out of context and I would get a few laughs.I guess it goes to show that boys grow to be men, but not really.