Brad Pitt helped Jennifer Aniston celebrate her 50th birthday.

Pitt was spotted at the actress’ birthday party at the Sunset Tower Hotel in Los Angeles on Saturday, PEOPLE confirms.

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Pitt, 55, made a casual entrance at the hotel, where his ex-wife, who turns 50 on Monday, held her big bash. The actor arrived at the hotspot with his long hair slicked back underneath a cap, photos show.

A source tells PEOPLE party guests included Pitt’s ex Gwyneth Paltrow, plus Aniston’s ex John Mayer and his ex Katy Perry, who was joined by boyfriend Orlando Bloom.

Image zoom Tony Barson/WireImage

Aniston also celebrated with her Friends costars and good pals Lisa Kudrow and Courteney Cox, whose ex-husband David Arquette attended.

Image zoom Brad Pitt BackGrid

The following day, Aniston’s pals began wishing the star a happy birthday on social media, sharing their own sweet images taken from the celebration.

“Love these ladies,” Hudson wrote alongside a series of photo booth GIFs on Instagram, in which she posed alongside Aniston and Paltrow. “Celebrated this beauty last night Happy Bday JA! We all love you sooo!”

In her own post, Paltrow wrote, “Happy birthday (last night and tomorrow) to #jenniferaniston our ray of sunshine, example of perpetual goodness. We love you so much and you make 50 LOOK🔥.”

Following the news of Aniston and ex-husband Justin Theroux‘s split in February 2018, a source with knowledge of Pitt and Aniston’s relationship told PEOPLE the stars — who were married from 2000 to 2005 — had “been over each other for longer than they were ever together.”

While Aniston and Pitt had remained friendly over the years, the source said the two weren’t especially close. “They aren’t in regular contact, beyond an occasional text back and forth to wish each other the best when there’s been a new project or big event,” the insider said at the time.

Image zoom Jennifer Aniston and Brad Pitt in March 2000 Bei/REX/Shutterstock

Pitt and ex Angelina Jolie called it quits in September 2016 after two years of marriage and 12 years together.

Nearly a year and a half later, Aniston split from Justin Theroux in February 2018 after two and a half years of marriage and seven years as a couple.

Image zoom Justin Theroux and Jennifer Aniston in February 2015 Jeff Vespa/Wireimage

Opening up about her personal life in the January 2019 issue of Elle, Aniston shared that even though her relationships with Pitt and Theroux didn’t last, knowing when to end a relationship has its own value.

“I don’t feel a void. I really don’t,” the Dumplin’ star told Elle. “My marriages, they’ve been very successful, in [my] personal opinion. 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.”

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“Sure, there were bumps, and not every moment felt fantastic, obviously, but at the end of it, this is our one life and I would not stay in a situation out of fear. Fear of being alone. Fear of not being able to survive. To stay in a marriage based on fear feels like you’re doing your one life a disservice,” she added. “When the work has been put in and it doesn’t seem that there’s an option of it working, that’s okay. That’s not a failure. We have these clichés around all of this that need to be reworked and retooled, you know? Because it’s very narrow-minded thinking.”

Aniston went on to share that despite the fixation people have about her marital status, she’s never placed a high priority on tying the knot.