I had terrible stomachaches as a child and when I was in about 2nd or 3rd grade my mother even took me to the doctor and I remember having barium x-rays done! Nothing was wrong and I think it was just nervousness, although I don't remember what I was nervous about. I also began having migraines as a child but I still have them (in fact I had one on Thanksgiving - yuck) but I don't know if stress is a trigger for me. I do currently know several kids, who are not necessarily gifted, who are having stomach complaints. In fact some of them are on Prevacid or other types of medicine for their stomach issues. So I don't know, but it does seem to have something to do with the age.