Are Jennifer Aniston and Justin Theroux Getting Married Today?

Is today the big day for the We're the Millers star?

Yes, we know it's supposed to be just a birthday party. So, why do rumors keep swirling that today's big to-do at Jennifer Aniston and Justin Theroux's house is actually their long-awaited wedding?

First, the official word from Theroux's rep:

"It's a birthday," the rep insisted to E! News around noon today. "Not a wedding. Today is Justin's birthday."

OK, and we do know that Theroux's 42nd B-day bash is supposed to be a big birthday party. But E! News has learned a couple of interesting nuggets. First, no-parking signs have gone up all along the Bel-Air street by Aniston's mansion, stating that there will be no stopping allowed from 4 p.m. to 11:30 p.m. Saturday. Also, at about 12:15 p.m. today, Aniston's hairdresser, Chris McMillan, arrived at the house.

Extra privacy, professional coiffure...for a birthday party? Stay tuned for more details as we get them!