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Brad Pitt Spotted At Jennifer Aniston's 50th Birthday!

Didn't see this one coming!!

Jennifer Aniston celebrated her 50th Birthday over the weekend with a star-studded event but there was one star who was there that everyone is talking about; none other than Brad Pitt!

That's kind of a big deal... if you remember, the two were married for 5 years before Brad Pitt allegedly had an affair with Angelina Jolie, and later went on to marry her.

A source said Aniston put her ex-husband on her invite list weeks ago and Pitt was in town and happily chose to attend to help her celebrate the milestone birthday.

"Jen and Brad have remained friends and have spoken with each other quite a few times since they both became single. They are friends and have supported each other through some tough times. They've come so far since their marriage and plan to stay friends for life. There are truly no hard feelings between them... They both realize that anytime they cross paths people talk about a reunion. He came on his own and quietly entered the party. They had heavy security, kept a ban on social media, and hoped for the best." 

Pitt is currently in a bitter custody war with Angelina Jolie, but at least he seems to be on good terms with one of his ex's.