Hiya, Jenny! You're as welcome as can be here at
planDisney!
According to the
General Walt Disney World Property Rules, all children under the age of seven must be accompanied by another Guest 14 years or older. Unfortunately, this means that your twins will not be able to ride together without your supervision. However, there are plenty of attractions throughout the Resort that you'll be able to enjoy together as a family! I'll give you a few examples so I can put your mind at ease.
At
Magic Kingdom Park, your options include but are not limited to Pirates of the Caribbean, Jungle Cruise, Haunted Mansion, the Walt Disney World Railroad, Peter Pan's Flight, The Magic Carpets of Aladdin, Prince Charming Regal Carrousel, Mad Tea Party, Under the Sea - Journey of the Little Mermaid, "it's a small world", The Many Adventures of Winnie the Pooh, Dumbo the Flying Elephant, the Tomorrowland Transit Authority PeopleMover, and Buzz Lightyear's Space Ranger Spin. At
EPCOT, you can enjoy all shows, Journey Into Imagination With Figment, Turtle Talk With Crush, Frozen Ever After, Journey of Water, Inspired by Moana, Gran Fiesta Tour Starring The Three Caballeros, Spaceship Earth, Living with the Land, The Seas with Nemo & Friends, and Remy's Ratatouille Adventure. At
Disney's Hollywood Studios, you have all shows, Toy Story Mania!, and Mickey & Minnie's Runaway Railway, and at
Disney's Animal Kingdom you can experience all the shows, Na'vi River Journey, and Kilimanjaro Safaris. Depending on your kids' heights, this list could very well expand!
Keep in mind that, for all attractions and experiences listed above, you'll be able to ride or sit together. However, that could look like all five of you sitting together in the same row or attraction vehicle or in two separate rows or attraction vehicles. While you could all sit together at Living with the Land, for example, you will definitely need to split into two groups for Haunted Mansion. Walt Disney World is very family oriented, so this won't be an issue during your vacation whatsoever.
I hope this helps, Jenny! If you have any other questions for us, please don't hesitate to come right back. We're always available and more than happy to help here at planDisney. See you real soon!
Warm hugs,
Ana Paula