If I was this child's mother I would be getting him up early in the am and inserting a suppository and then waiting a few minutes (5-10) and put him on the toilet and telling him to stay there till he goes. That way he's all cleaned out before he comes to daycare. This child is using it as a control issue. There are things in his life that he can't control such as his parents separation for one and it could be causing him stress but his bowels are something he can control so he is. He's choosing not to use the toilet.