Speaking of their current relationship, the source said, "Brad and Jen talk or text once in a while".
We chose to look back at Jen's transformation through the years to mark her 50th birthday.
The next day, Aniston's high profile pals gushed about the previous night's celebrations and wished the actress a happy birthday for her actual birthday, which is Monday February 11 (today in Australia).
The 55-year-old arrived at the star-studded bash at the Sunset Tower Hotel in West Hollywood on Saturday wearing a flat cap and quickly made his way inside.
'Brad, for long, was a very important part of Jen's life.
While we don't have any photos of Pitt inside the event, a few of Jen's celebrity guests broke the "No Social Media" rule - "with permish", according to Kate Hudson - to share some pictures from the party's photo booth.
Rese had partied until the early hours with the likes of Gwyneth Paltrow, Laura Dern, Sandra Bullock and Courteney Cox and had appeared to have over-indulged as she made a very bleary-eyed exit from the party. The source from People commented that while the two were seen chatting and having a good time, Aniston wanted to make sure all of her guests were happy.
In an interview for the January issue of Elle magazine, Aniston also spoke on their 2018 breakup.
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.
She said: "I don't feel a void". I really don't. My marriages, they've been very successful, in [my] personal opinion.