My 3 year old male kid is having the problem of chronic constipation. He does not go to potty 3 days continuously and then from 4th day, he starts soiling underwear (little poo in the underwear almost 7-8 times in a day). If we give him sodium pico sulphate 5 ml in the night, next day he would go to potty 5-6 times. Other laxatives like lactulose are not having any effect on him. He has been suffering from this problem for last more than one year.