bowel control in Duschene's M. D.

I am the teacher of a six-year-old boy with Duschene's M.D. We are struggling to know whether his difficulty with getting bowel control is out of his control, or if he is able to know when he is going to have a bowel movement and just doesn't want to stop playing to go to the bathroom. He often goes on his own for urination, so I think he would want to go for bowel movements too. Any thoughts?? Thanks! Chris