"Jen didn't really pay any special attention to Brad", the source says.
He made a casual entrance at the hotel, with his long hair slicked back underneath a cap.
A source apparently confirmed to People that Aniston's ex-husband was, indeed, in attendance.
Besides her very public personal life, Aniston is best known for her breakout role on the TV show "Friends", where she starred as Rachel Green on the late-90s/ early 2000s sitcom. As per sources, Brad was invited to the star-studded party by someone else. According to a report by PEOPLE, Pitt showed up at his ex-wife's bash, celebrating her 50th birthday, which is on Monday.More news: Kylie Jenner and Travis Scott wrapped in love at the Grammys 2019
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As Rachel Green, she became a household name and then a bona fide movie star; she saw her love life become incessant tabloid fodder; married Brad Pitt, then famously divorced him; and years later gave matrimony another go with Justin Theroux.
It is believed she ducked out of her birthday bash at around 1am in the morning.
Speaking recently about the show, Jennifer told Entertainment Tonight: 'I just keep pinching myself, from this to that I just don't know what to say.
While Aniston and Pitt had remained friendly over the years, the source said the two weren't especially close. And when they came to an end, it was a choice that was made because we chose to be happy, and sometimes happiness doesn't exist within that arrangement anymore. To stay in a marriage based on fear feels like you're doing your one life a disservice. Pitt's 12-year relationship with actress Angelina Jolie ended in 2016 after two years of marriage.