Hello, There is a type of constipation in which the stool accumulates in the bowel so much that it enlarges the bowel. Then soft, liquid feces above leaks around the stool below and comes out the anus soiling your son s underpants. This is known as overflow incontinence. And can be associated with urinary incontinence. Once the stool problem is fixed, control of urine often follows. Some physicians recommend giving the child a stimulant laxative such as senna. It causes the colon to move in a wave-like motion. It comes in tablet, liquid, and drops. You can start with one tsp of the liquid or one ml of the drops by mouth once a day. Then increase the dose by one-half tsp or one-half ml every couple of days until the dose is reached that empties the colon. Side effects of medicine are belly pain, nausea, and diarrhea. It is over-the-counter. Be patient. It is a long process and could take months. Some children are helped if they are given a star chart so they can place a star on each day they stay clean. Sometimes doctors feel that a parent should not make the child clean up his mess. This makes the child feel as if he is being punished. Do not blame him. If problems persist, please return to Healthcare Magic or let him be evaluated by his primary care physician. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Arnold Zedd