DD's birthday is December too (and DS in November). We took a trip to an indoor watermark for one of their birthdays. One time we stayed local, but let DC choose a day of activities - fav restaurant for lunch, out to movie, bowling, etc.
My DD has talked about just me and her going to a hotel to spend the night, getting pedicures, eating out, etc.
SAHM to Pete and Repeat my "Irish Twins" - DD 12/06 and DS 11/07
Never argue with an idiot. He'll bring you down to his level, then beat you with experience.