My sim does get invited to birthday parties. There doesn't seem to be any other type of parties happening on home lots, but that's ok I think. They get invited to dance parties very often lol.. I think it's better now than in the Sims 3, though. There were parties happening all the time which kind of bugged me. I don't really go to birthday parties now that I'm playing with aging off and deciding for myself when my sims and townies age up, because that takes that control from me. But to make you feel better the birthday parties aren't that much fun. If the birthday sims' house is ill equipped it just turns into sims getting angry and sometimes the caterer bugs out and never makes a birthday cake, which ends in the party being "a failure". So yeah.
