Hello Diana! Welcome to the Disney Parks Moms Panel.
It sounds like you have a wonderful birthday experience planned for your Aunt at Liberty Tree Tavern in Magic Kingdom.
Walt Disney World Resort Dining Locations are ready to help
make any celebration extra-special for their dining Guests. You can
arrange for a specialty cake to be delivered to the table by calling (407)939-3463 and adding the request to any future
Advanced Dining Reservations.
Additionally, you can make a request in-person at the restaurant directly upon your arrival on the day of your visit. While all Dining Locations at Walt Disney World Resort have supplies of celebratory treats on-hand, I recommend that you schedule yours in advance as treats are available on a first-come, first served basis if you wait until the day you arrive.
As far as smaller treats, speak with the Cast Member when you arrive at
Liberty Tree Tavern to arrange a smaller dessert to arrive at the table to celebrate your Aunt's birthday.
Have a Magical Celebration!
~Todd