It is wonderful that you're beginning your planning now. The Grand Gatherings special events allow only a limited number of people and - especially at Christmas - can really fill quickly. You'll want to make the reservations as soon as possible. They don't necessarily have the same reservation window as the other dining and special events so you'll want to be sure to ask.
You may find it helpful to use a travel agent who specializes in Disney vacations - especially when juggling so many people. We used www.buildabettermousetrip.com and were very pleased with the service. There is another agency associated with this board too.
Our Authorized Disney Vacation Planners are here to provide personalized, expert advice, answer every question, and uncover the best discounts.
Let Dreams Unlimited Travel take care of all the details, so you can sit back, relax, and enjoy a stress-free vacation.