My son is getting very stubborn and cranky When asked to sit for potty. He doesn't want to go to the toilet he cries a lot. He tells when he wants to pee but not when he has to poop. Ha has started to hold his poop if he is not wearing diper which leads to hard poop and constipation later. I started his potty training when he was two. Now he has turned two years five months still he fears to go to the toilet. What should I do?