My child is 3.5 years old . He is not potty trained yet . He has no problem with doing urine . He goes to washroom for urine and tell whenever he wants to go for pee even in night also . But for poop he only do with his pants on .He tell that he wants to peep but If we remove his pants he hold potty . And donot do for several hours if we keep him without clothes . He do his potty only in clothes . Any suggestions to change his habit !!