Hi there, Blanca!
What a magical birthday week your son will experience at the Walt Disney World Resort! There is no need to worry about proof of age just let the Disney Cast Members know your prince is only two. His age on the first day of your visit to the Walt Disney World Resort is his age for the length of your vacation.
Be sure to pick up a birthday button for him to wear the entire week so everyone can wish him well! I also suggest a set of birthday-themed Mouse Ears for him to wear and to save as a keepsake. You can have his name embroidered on the back at several locations throughout the parks, but my favorite is on Main Street, U.S.A. at The Chapeau. You may also want to consider ordering a special cake for his special day! We are planning on celebrating my daughter's birthday on our next visit, and I've been eyeing the
new Mickey Mouse Celebration Cakes that can be ordered at any Walt Disney World Resort owned-and operated table-service restaurant. And if you want an extra dose of pixie dust for your prince, please check out
Disney Floral and Gifts to order in-room decorations and surprises!
No matter how you celebrate, I know it will be magical, Blanca! Please let us know if we can help further with your pixie-dusted plans and Happy "early" birthday to your son!
Nancy