What is the current custody agreement? Given the minor is intellectually challenged and there will be more than one flight involved an unaccompanied minor program will likely been an issue. The bigger issue is getting the child proper documentation and also having a custody agreement for the child. To fly home the airline will most likely need to know that the mother is deceased and the father has legal custody of the child. I would suggest you contact the embassy or consulate in Ghana to find out what paperwork will be required for the child to return to Canada.