Hi wishatsea, and welcome to cruise-chat.
I found the following thread on our Disabled Travel Forum, and hope it is of some help to you. One of the posts (the last one, presently) has a link to information specific to Royal Caribbean:
http://cruise-chat.com/eve/forums/a/...2/m/5761039672
I'll look into your ports of call so that I may try to offer suggestions.
Sonny, will they need to rent a power wheelchair if they are bringing their own?