Hi Pamela!
Thank you for bringing your question to the Disney Parks Moms Panel.
Cinderella's Royal Table is certainly the perfect spot for your Princess to celebrate her birthday!
Your best option is actually going to be to try and make your Advanced Dining Reservation online first. The window for Advanced Dining Reservations opens up online 6 AM EST. The window for folks attempting to book over the phone will then open up at 7 AM EST. I would recommend logging into your
My Disney Experience account and trying first to
book online. If you have difficulties, you can always try to call afterwards, but I think you'll find that booking online is incredibly easy and often much quicker!
If you will be staying on property and visiting Walt Disney World for multiple days, you'll likely find there is more availability later into your trip. Since Guests are able to book 180 days out plus up to 10 days of reservations for their stay, you'll find the further out into your window you book, that less people have this ability.
Please come back and let us know if we can help you plan your daughters special trip in any other way!
-Lindsey ºOº