including Brad Pitt.

The Morning Show star, 50, had a tree trimming party on Saturday, which was attended by a star-studded list of guests, including Gwyneth Paltrow, Kate Hudson and Jimmy Kimmel — as well as her ex-husband, a source tells PEOPLE.

“The annual tree trimming party is always Jen’s favorite to host,” the source says. “She loves Christmas. As usual, a large group of friends attended.”

Regarding Pitt’s appearance, the source adds, “They have been in touch a few times since her birthday and are keeping it friendly.”

Back in February, the Ad Astra star, 55, also attended Aniston’s 50th birthday party, which was held at the Sunset Tower Hotel in L.A.

An insider told PEOPLE at the time that his appearance came simply because the former couple, who were married from 2000 to 2005, has a “very civil relationship.”

“He would not have been asked to come if that weren’t the case. It was a big night for Jen,” the insider said. “The important people in her life gathered to celebrate with her. Brad fits into that group, and it was natural that he would want to come.”

RELATED: Jennifer Aniston Is ‘Very Happy’ Brad Pitt Attended B-Day After She ‘Debated’ Inviting Him: Source

Following their split, Pitt married Angelina Jolie. They called it quits in September 2016 after two years of marriage and 12 years together.

Aniston, meanwhile, split from Justin Theroux in February 2018 after two-and-a-half years of marriage. The pair have remained close, with Theroux being one of the many guests at annual Aniston’s Friendsgiving dinner last month.

After Aniston and Theroux’s divorce, a source told PEOPLE that reconciliation between Pitt and the actress was highly unlikely.

“For well over a decade now they have lived totally separate lives and so not surprisingly, they have become totally different people than who they once were when they were together,” the source said. “They’ve been over each other for longer than they were ever together. It is such ancient history.”

Pitt has also brushed off any notion of reconciliation. In a video shared by Entertainment Tonight in May, Pitt laughed when a paparazzo asked him the one question “everyone wants to know”: is he getting back with Aniston?

“Oh my God,” Pitt said, before hopping in his car and telling the shutterbug, “Alright, have a good one.”