I am a Utah attorney, so this opinion is based upon Utah law. If your Decree of Divorce does not provide what happens in the event the custodial parent is incapacitated, and if his parents are being jerks about it, file a motion with the court seeking a temporary change in custody. As long as you're a fit parent, you should get the temporary custody easily, especially since your ex/his parents tried to keep his incapacity a secret.
Answered on Dec 24th, 2013 at 3:19 PM