Hi, Kristin!
I can't think of a more magical way to celebrate your daughter's birthday than by going on trip to Walt Disney World!
Mickey's Not-So-Scary Halloween Party happens to be my all-time favorite Special Event on the planet! I just love how the entire Park magically transforms into a happy, haunted wonderland!
If you are purchasing your daughter's costume at home prior to your vacation, you can actually ship it to arrive at your Resort hotel by writing the words "hold for guest" near your name and "arrival date xx/xx/xx" on your shipping label. If you plan on purchasing the costume at Walt Disney World, you could try talking with a Cast Member at the front desk of your Resort hotel and ask if it could be placed in your room once you leave one morning.
Another idea is to hide the costume in your room and when you all leave together, one of the grown-ups in your party could
pretend that they forgot something in the room. That person could then get the costume out real quick and lay it out on the bed for when you return to your room that evening. Imagine the excitement on your daughter's face when she sees that it magically appeared?
I sure hope this gives you some ideas, Kristin! Please don't hesitate to let us know if you have any other questions we can help with!
Please tell your daughter Happy Birthday from all of us at the Disney Parks Moms Panel!
Wishing you a Pixie Dusted vacation!
~Jackie