Hi Tiffany!
How exciting! I still remember the first time I took my kids as babies to Walt Disney World. Such great memories were made! I live for my TimeHop app to show me those photos from years ago.
Parking at Walt Disney World could be a little tough for your sister with infant twins and toddler in tow. If she parks at the Ticket and Transportation Center, which is the parking lot for Magic Kingdom Park, she will still need to take the monorail or the ferry boat to the park. Preferred parking will get her closer to the monorail and ferry loading areas so at least she will be able to skip the parking lot tram. Assuming she will have a stroller (or two?), they will not need to be folded for either of these modes of transportation, so that's good news!
The faster and closest option is to use the
Minnie Van Service. The Minnie Vans use the Disney bus drop off area, which is super close to the entrance to the park. You eliminate the hassle of parking and then taking another mode of transportation to get to the park entrance. Minnie Vans are driven by Disney Cast Members and each van is equipped with up to 3 carseats, including rear facing carseats for the littlest of guests.
The easiest, less of a hassle option would be to take a Minnie Van for sure. If this is something you are interested in, you can pull up additional pricing information while you are at your Walt Disney World Resort hotel through the Lyft mobile app on your phone.
Please stop back by if you have any additional questions.
Have a magical day!
Leslie