It's great to see you here today at the Disney Parks Moms Panel, Jennifer! How exciting that you're going to be visiting The Most Magical Place On Earth in just a few days, and that your lucky niece gets to join in on the fun as well!
The drop-off area for
Magic Kingdom Park is located at the Transportation and Ticket Center, which is also where you park your car for the day. Your niece's parents will be able to drop her off there without having to pay but she will have to make a short journey by
ferry boat or
monorail to get to the entrance gate. You didn't mention how old she is, but be aware that she would need to be able to navigate using the transportation by herself and take a 10 to 15-minute journey to meet you and get her ticket. If she's too young or doesn't want to travel on her own that's totally fine and you still have a few options. You can leave the Theme Park and meet her at the Transportation and Ticket Center so her parents can drop her off without paying for parking, or her parents can pay to park their vehicle and escort her to meet you. You don't need
Theme Park admission to ride the ferry boat or monorail so all three of them would be able to travel together if that's what they want to do.
I hope this answers your question, Jennifer, and please let us know if there's anything else we can do to help you plan your magical day!
Jessica