is half way potty trained with peeing on the potty like it is no big deal anymore. He has went poopy a couple of times on the potty but nothing consistent. I want to start back to law school in January and send him to the Montessori school in Dec but he has to be potty trained by that time. I have showed him how to do it and let him watch videos of using the potty and praised him when he did but cannot get him to go. When I know that he has to go I hurry and sit him on the potty but he holds it in and refused to go. Then when he has a diaper on he has a humongo. I called the DR today and asked if there was anything that I could give him to make him go besides milk of mag or anything else that would make him go so I could know when to expect him to go so that I could have him sitting on the potty at that time and praise him when he does, but she said that there is nothing. She said that I have already tried everything that she always recommends and just to give it more time.
Anyone else have any suggestions that worked for them with their kids? Or does the nurse have any suggestions?

Thank you