Welcome Danielle, thanks for visiting us at the Disney Parks Moms Panel.
You gave your daughter the best Christmas gift ever! Visiting
WDW during holiday season is very special. Your family will make memories that will last for a lifetime!
If your mother is sharing the same room with you and your daughter, I believe you will have no problem to add her to your existing reservation. At
Disney Resort Hotels, you will be charged per room, not per person and most of the rooms can accommodate up to four adults.
Any changes regarding existing hotel reservations have to be done by
calling WDW. You can include her to your reservation, and also add a Disney Dining Plan and Theme Park Tickets if you desire. Cast members will be glad to assist you.
Come back to visit us again soon.
Wishing you a wonderful day!
Gina V.