Hi Stephanie!
Welcome back to the Disney Parks Moms Panel. I absolutely loved the Beauty and the Beast theme from the 2017
Disney Princess Half Marathon Weekend!
For the race this past year, the theme was released when runDisney revealed the medals! This was released on the
Disney Parks Blog on December 5th. While it isn't guaranteed that it will come out exactly at the same time this year, last years information is the best we have to go on. If you haven't already, I would recommend subscribing to the Disney Parks Blog to stay up on all the latest information related to everything Disney. Another great source is to follow @runDisney on Twitter and Instagram. They'll usually release images there too and that'll be your alert to check out the Disney Parks Blog.
I'm glad to let you know though, that your costumes most certainly do not have to match the theme. I've seen mashups were runners will combine there favorite Disney Princess and Star Wars character into a uniquely awesome costume! I do understand if you want to wait though so your medals and ensemble are completely coordinated.
I truly hope you and your daughter have a magical time. Please let me know if I can help in any way before your trip next February!
-Lindsey ºOº