My almost 4 year old son will go peepee on the potty all the time but when it comes to pooping he will go on himself then sit on the potty. He for a good month and a half did wonderful, then just stopped and nothing has changed home environment wise. And he also still every once in a while goes on the potty without going on himself first. We have tried rewards, stickers, m&m's. His 2 year old sister is completely daytime trained, but he just isn't and and I am at my limit.