Hmm. Maybe it's because "tummy" or "belly" just sound really silly to me...I know stomach is just the internal organ, but it's the word I've learned (my parents almost never say tummy or belly either, now that I think about it!) *shrug*
Yeah usually I hear it when people ask kids 'oh does your tummy hurt?' I was soooo happy to hear my little 3 yr old niece saying 'my stomach hurts' all weekend. Well, not happy that her stomach hurt of course, but happy she used the term stomach!
It seems like tummy also refers to the internal organ as it's just a nickname for stomach. Belly - ok that one yeah maybe, but still it's a dumb word. When I went to the doctor and they told me I had too much fat around my waist, I think they called it 'belly fat'. GROSS! I just keep saying 'around my middle' or 'waist'.
My weird thing is I wash my hands about a million times a day. I don't have OCD or anything, just a habit.
Spending a week with my nieces and nephew again showed me that the oldest (6 yrs old) also has this washing hands thing. The problem is it is causing her hands to get all red and chapped. I feel really bad for her but it is just something she keeps doing. I hope she'll grow out of it. My sister and brother in law try to limit it but she still keeps it up.