Avoid dairy products....get done stool routine.

Besides this complaint how Is he ? Is he active , playful takes interest in people with age appropriate mike stones ? Keep a record of weight . If all is good it must be a case of over feeding . But to rule out other causes You should do stool examination which can detect undigested food particles , worm infestations , microscopic blood. , acidic ph of stool etc. depending upon what lab finds he can be treated by us doctors

Since how long dis problem is going on?? How much he has gained weight in last 6 months? Is it associated with pain in abdomen?? If child.is playful and active with no complaints, just relax. Decrease milk amount in the diet.