Welcome BACK, Ashley!
This is a great question with an even better answer - the iconic Disney 'Mickey Ear' Balloons stay inflated forever! Well, okay, not actually forever. But they do stay inflated anywhere between three and six weeks. (We currently have one floating in our living room that we bought three weeks ago that is still going strong without any signs of stopping.)
There are a few different balloon options: the
iconic Mickey Ear balloons come inside a clear plastic outer shell to help protect the latex ear balloon inside, but you'll also find the foil-ish mylar balloons themed to different characters and movies. My personal favorite are the white Mickey balloons with a battery operated color changing light wand on the inside. Not only are these fun, but they are so super helpful when trying to locate your stroller at night! Pro Tip: The light up balloons are usually sold in the late afternoon or early evening, and are typically found in Magic Kingdom Park, but I've definitely purchased one at Disney Springs this year, and I think I recall seeing them at Disney's Hollywood Studios recently. When the balloon has reached the end of its life, you can carefully cut it's string and keep the color wand for other purposes. And bonus info, should your balloon pop at any point during your vacation, you'll be able to trade it out for an identical balloon.
You will absolutely be able to bring these cheerful pops of color with you back into Disney's Theme Parks during your stay with one exception: Disney's Animal Kingdom Theme Park
does restrict plastic items like straws and balloons that could end up in the animal habitats. Other than that, your balloon is free to see the World (well, the Walt Disney World Resort) with you!
I hope this helped in planning your Disney Days, Ashley, and We'll See You Real Soon!
~Kristen