First of all, in case you don't know this forum is made up of people with health problems that come here to support each other. We aren't doctors. But we understand what it is to worry about health problems, whether in ourselves or in loved ones. So, I will attempt to help you.

I don't know for sure why your son has a prominent belly. If your doctors have checked him out, maybe his large belly is genetic. Does your son's father have a large belly? I've seen children with large abdomens who were perfectly healthy. They were just built that way. I don't know how large your son's is, but maybe your are comparing him to what you know.

I know that some of the things that can cause an enlarged abdomen in children are enlarged liver and malnutrition. If your son had these problems, you would know it because he would have other problems as well. Again, these would be things that would be easily diagnosed by a doctor.

As long as your son is healthy and has no complaints of pain or weakness, and he has a good appetite and can run and play like other children, perhaps you shouldn't worry about it.