I have lots of holidays. I have four weeks in each season and three out of the four have a holiday of some sort. There are a few small ones like Parent's Day that just have a couple of traditions and no real decorations, and then all the major real world US equivalents (Christmas, Halloween, Thanksgiving, Easter, New Years) and a few that are just about going on vacation or traveling off lot.
I play rotationally, and each rotation my sims age about 2 years, and I envision that I am playing a week of their life during that two year period, so every family doesn't celebrate every holiday every time, just whatever their week happens to be. I usually choose the order I am going to play my families in based at least partly on what holidays they'll be celebrating. I like children in the household for Winterfest and Blossomfest, and older parents for Parents Day, and I try to spread it out so every household gets to every holiday over time.
They dont line up with the real world all that often for me. I do happen to be playing summer right now but I probably won't get to my labor day equivalent by the end of this weekend. Then I'll probably get through all of the fall holidays and maybe even Winterfest before the end of September.
