Hi Sarah!
Welcome to the Disney Parks Moms Panel! Walt Disney World Resort is a fantastic vacation destination for the whole family, including the smallest members! We took our son on his first trip when he was 8 months old and he really enjoyed the rides, shows, and parades. You will be able to take your little princess on any of the attractions in Magic Kingdom that do not have a minimum height requirement. Take a look at this
Disney Parks Blog post for a list of the height requirements for the attractions in Magic Kingdom. (There are 25 for your family to enjoy!) My son's favorites from his trip were Buzz Lightyear's Space Ranger Spin, Under the Sea ~ Journey of The Little Mermaid, and The Many Adventures of Winnie the Pooh.
Be sure to check out the
Baby Care Centers on your trip. I found them to be a great place to take care of my son's needs, enjoy the air conditioning, and get a break from the hustle and bustle of the park.
Please let me know if you have any other questions as you get ready for your trip. T-T-F-N, ta ta for now!
~Crystal B.