Our 3-year old son is doing well with potty training in regards to staying dry and in undies all day, going when he needs to go on little or big potty, etc. But we have run into an issue with bowel movements...he only does them at nap or at night when alone and when he is in a pull-up (he still wets some nights). I have spent numerous hours recently having him sit on the potty to try and go, but so far it is a no-go. He verbalizes that he is afraid to poop. Any suggestions greatly welcomed.