hi, thank you for your query. Distended stomach in children is not something to worry about. At times, it can happen due to overeating. Their stomach may also get distended if they use straw for drinking, talk a lot while eating or they try to finish off the meals in a hurry. In all such conditions, they actually swallow up a lot of air through their mouth and that triggers stomach bloating. If it happens on a regular basis, it could be a sign of some undiagnosed health problem. some of the other causes are- 1.lactose intolerance 2.celiac disease 3.constipation 4.giardia infection you can get a Physical examination of the abdomen, studying of the symptoms, laboratory test of stool samples are important part of diagnosis. The treatment is then based upon the underlying cause. it is not a condition for concern. thank you, wishing you good health