Hello Jennifer and welcome to the Disney Parks Moms Panel!
I had to do some research to find out why the park is closing early on April 17, 2018. A Cast Member told me the Magic Kingdom Park is closing at 6:00 P.M. for a private event that evening. The entire park will close at 6:00 P.M. including shops, restaurants and attractions.
The night will still be young and there is plenty of magical options for a fun evening at the Walt Disney World Resort. If you are a Resort Hotel guest with Park Hopper Passes, you can enjoy
Extra Magic Evening Hours at Epcot until 11:00 P.M. If it is shopping you are looking for,
Disney Springs is the place for you. Lots of shopping, dining, and entertainment opportunities to explore at Disney Springs. If you have any more questions about your trip, be sure to come back and visit us here at the Disney Parks Moms Panel.
See ya real soon,
Andrea