The person who is making the reservation in their name is the one who is supposed to have the AP. I would think that you cannot make a reservation in a child's name, so the adult would need to have the AP... That being said, I made my ressie for a September trip with an AP which I purchased upon my arrival at the Disney Magic store at MCO. When I checked into PC, I was never asked to show my AP, even after the castmember mentioned that I was checking in with an AP rate...I wouldn't suggest trying to check in without the AP in my own name. You could end up being turned down and charged full rate for your room....Yikes!!!