Sometimes some intestinal issues crop up from nutrition - and kids who are picky eaters (even just a little) are often missing nutrients. And the AMA has said (10 years ago) that our food supply is deficient, even if we eat organically, so everyone needs a little help. I have friends with young kids who had a lot of problems, and found a product that works. It's delicious so you don't have to force them to drink it - they like it. Probiotics are great if you can get him to eat them, but they don't always do the whole job. Intestinal issues can show up as diarrhea, constipation, or a combination of both on an alternating basis. There is help - let me know. If this doesn't work, you can get him checked out - obviously it could be something else, as others have suggested, but before you go through a whole lot of elimination diets (no dairy, no wheat, no this, no that), you can try ADDING what's needed to digest properly. Elimination diets are hardly ever necessary, and they are a real pain. I'm a nutritional consultant and have worked with a lot of people - happy to talk to you.