My three year old little boy has been potty trained for a whole year. He doesn't even wet the bed at night. He never has accidents, but around Christmas this past year he started holding back the urge to go poop. You can tell when he's doing this because he walks funny, but you can ask him if he has to go and he says no. I usually then make him to go sit on the toilet but he rarely does anything. He holds it to the point that it smears all in his butt and in his underwear. I've tried rewards, praising him for going to poop, and punishing him by no t.v. or putting him in time out. Nothing is working. Any suggestions? Anything is appreciated! Thanks!