Hi Victor!
You are picking one of my favorite times of year to visit! The fall decorations are all around Walt Disney World and Halloween activities are in full swing.
My favorite special event at the Magic Kingdom is
Mickey's No-So-Scary Halloween Party. Your Princess will have a spooktacular time dressing up and trick-or-treating around the park. There are special dance parties, character meet & greets and a fantastic special parade and fireworks show. This event does require a separate ticket for admission and I highly recommend purchasing tickets in advance.
Bibbidi Bobbidi Boutique is always a special treat for little girls. Your daughter can be part of her very own fairy tale with this royal makeover. There are two locations to choose from: Magic Kingdom or Disney Springs. Both locations require advance reservations.
How about a special souvenir? One of my most memorable souvenirs from when I was a little girl visiting the Magic Kingdom is my personalized parasol umbrella. These parasols are hand painted and completely customizable. My daughter uses it for her dolls now.
Whatever you decide to do, your Princess will be sure to have an unforgettable time.
Have a magical day!
Leslie