What i am trying to do .because my three old girl knows when she has to go to the bathroom but she don't want to she thinks she is still a baby.she always a pull up on.then she was bout to run out and i didn't go by her anymore pull-ups.because she has a drawer full of underwear in her room.but she don't ever wanna wear them she wants to wear pull-ups.so when she ran completely out I'm put underwear on he and i put a plastic bag under where ever she was and last night i put it on her bed and did not wet the bed.and i woke up to use the bathroom.but it didn't work.but this morning she used the potty like a big girl.but i don't know if it worked i will see though.hope fully it does.what i have figured out is that yo have to think outside the box when it comes to potty training.i hope i was help.

Often @ the age of 4, bowel movements come at the same time. If you know when that is, have him sit on the potty til he has his regular bowel movement. When he does have a bowel movement in the potty chair, make a HUGE deal of it.  Whoop & holler & cheer & clap for all in the house to hear & join it!  Also, you can try the reward system of letting him pick out new BIG BOY undies when he stops going poop in the diaper. I would also reinforce that pull ups are like diapers & that he is a big boy. If you find this successful& let HIM choose (touch hold, carry) the undies he chose. Make it a big deal!