Jennifer Aniston had a blast on her birthday with her friends.

The "Cake" star turned 49 on Sunday. Aniston's husband, Justin Theroux, was not able to spend the day with her as he had to attend New York Fashion Week, but the "Friends" alum still enjoyed her special day with her close pals in Malibu, California.

According to People, Aniston spent her birthday with her pals Courtney Cox, Andrea Bendewald, Leigh Kilton-Smith and Kristin Hahn. The "Horrible Bosses" star's manager, Aleen Keshishian, shared a snap of the girls celebrating Aniston's special day.

"#happybirthday to my sister from another mother #jenniferaniston [heart] u so much!" Keshishian wrote.

Other celebrities and showbiz pals also took the time to greet Aniston on her birthday via social media. "Happy Birthday to my work sister #JenniferAniston !! Wishing you a day filled with lots of love and laughter! #HBD," Reese Witherspoon wrote on Twitter.

"A huge happy birthday to the hilarious and talented #JenniferAniston!" Warner Bros. UK wrote.

Aniston's birthday celebration this year is low-key compared to last year's bash. In 2017, the "We're the Millers" star flew to Los Cabos, Mexico for her special day and celebrated with Cox and Theroux.

Although Theroux was not present during his wife's birthday celebration this year, an insider said that their marriage is going strong. While Aniston and Theroux do spend most of their time apart, this does not seem to be an issue for them.

"They have figured out a life that works for them," a source told People. "Jennifer's life with Justin is great. By not spending every minute together, it's like their honeymoon is lasting longer."

"This has not hurt their marriage at all, it seems to help," another source from the entertainment industry added. "They love and respect each other and do spend a lot of time apart. For them, it is a healthy part of their romance."

Last year, there were rumors that Aniston and Theroux were having marital problems. Aniston and Angelina Jolie were reportedly also feuding over another man, Ted Sarandos. But Gossip Cop debunked the reports claiming that Aniston and Jolie are competing for Sarandos' affections. Both have no romantic ties with Netflix's chief content officer.

In addition, Aniston and Theroux have already discussed her preference to live in Los Angeles and his fondness for New York. They agreed that it was not an issue. In fact, they are filled with love and laughter whenever they are together. The couple is also not bothered by the rumors because "they don't let all speculation get to them."