Hi, Debby!
As a mom, I certainly understand wanting to plan and provide for your children -- especially when there are allergies and special requests involved. My best advice to you is to
over communicate with the Disney Cruise Line (DCL) cast and crew in order to be accommodated.
First of all (if you haven't already), make sure you complete and send a
Special Services Information Form. There really isn't space to outline your son's allergies. However, I would complete the personal information at the top and list specifics at the bottom or on the back. Make sure you get this form to DCL at least 30 days prior to your sail date and provide contact information so that a member of the team may be able to contact you.
In addition, you may want to have your questions answered by booking agents who know the capabilities of the ships when accommodating guests with food intolerances. You can call that Special Reservations Line at (407) 566-3500 or send an email to DCL.Special.Request.Medical@disney.com. I know that special dietary requests can be made of the dining restaurants on board but not in the quick-service areas, and I'm not certain of the accommodation abilities of the resources on Castaway Cay. You will definitely need to maintain a dialogue with the special requests team before and during your cruise as well as remind the dining staff once you're on board.
I sure hope this has helped you, and I hope that your vacation is as worry-free as it possibly can be for you as a mom. Let me know if there is anything else I can do to assist you. Have a wonderful day and a magical vacation. Bon voyage!
Andi