We can go friday 12/13 or sunday 12/15. just wondering if anyone has any advice on which day might be better in terms of crowds? It seems like the holiday season really ramps up that weekend so they might be about the same?
Friday parties tend to be the busiest of the week, so I would choose the Sunday one.
They wrote a blog about the best & worst dates: https://touringplans.com/blog/2019/07/25/finding-the-least-crowded-mickeys-very-merry-christmas-party-in-2019/