It's no secret that Friends is one of the greatest and most beloved sitcoms of all time. It's charming, funny, and depicts moments that many people go through in their 20s and 30s. What makes it such an infinitely rewatchable sitcom, though, is the fact that the main characters formed long-lasting friendships outside of the show, making the series itself feel even more real and authentic.

RELATED: 10 Fan-Favorite Outfits From Friends That Are Still Fashionable Today

Monica and Rachel were former childhood BFFs when they reconnected in their mid-20s, but in real life, Courteney Cox and Jennifer Aniston began their friendship when they were cast on the show. They quickly went from being coworkers to friends to best friends, and have remained an integral part of each other's lives, even years after Friends ended.

They've Been Friends For Nearly 30 Years

Cox and Aniston first met when they were cast as BFFs on the NBC sitcom in 1994. They (along with the rest of their castmates) were encouraged to spend time with one another outside of the show to make their friendship seem authentic and genuine.

Nearly 30 years later, Cox and Aniston are still besties, frequently posting Instagram pictures together. They have stood by each other's sides through it all in the course of their 30-year friendship, consistently praising one another in interviews and on social media. For Cox's birthday last year, Us Weekly reported that Aniston posted a throwback video on her Instagram story that read, "Happy birthday to this ridiculously special human @courteneycoxofficial. Time flies when you're having fun!"

They Go On Vacations Together

In addition to spending countless hours on set with each other, Aniston and Cox have been known to hang out outside of a work environment. Much like how their characters took several trips together on Friends, the two actors have traveled together, making and documenting memories to strengthen their bond.

RELATED: Friends Characters & Who They Should Have Dated From The Office

The leading ladies have been photographed getting away in Cabo and Tahiti over the years. Most recently, the pair and their other Friends' BFF, Lisa Kudrow, (who played Phoebe Buffay) spent 2021's July 4th at a beach house together.

They Ate Lunch Together Everyday On Friends

One of the most common questions the Friends' cast used to get asked all the time in interviews was if they were really friends. Aniston and Cox always answered that they were, citing that they ate lunch every single day together on set.

They had so many lunches together that they began adopting each other's eating habits. According to E! News, "Cox revealed that she and Kudrow started eating the 'Jennifer' salad'—a Cobb but with turkey bacon and the addition of garbanzo beans—for lunch every day."

Courteney Attended Both Of Jen's Weddings

Jennifer Aniston has been married twice so far in her life, both to high-profile Hollywood actors. Her first wedding was in 2000 to Brad Pitt, and her second nuptials occurred in 2015 where she married Justin Theroux. Both times, Aniston's real-life Monica was in attendance.

RELATED: Which Friends Character Are You Based on Your Enneagram Type?

Not only was Cox present for Aniston's second wedding, she actually served as her maid of honor. According to an article from CloserWeekly, There were reports that Cox stayed at the wedding, partying through the night into the early hours. Fans can only hope that Aniston will be returning the favor at Cox's wedding to Johnny McDaid. Cox has reportedly been in a relationship with the Snow Patrol musician off and on since 2013.

Jen Guest Starred On Courteney's Show

Courteney Cox got back into the world of sitcoms in 2009 by leading TBS's Cougar Town. She played Jules, a recently divorced single mother navigating the world of dating after being married for so long. In the second season, Jennifer Aniston guest-starred, reuniting the two Friends' BFFs back together on-screen for the first time since the show went off the air in 2004.

Aniston played Cox's character's therapist, Glenn, in her one-episode arc. Glenn and Jules quickly formed a close bond, which bothered Jules' 'Rachel' of the show, Ellie (Christa Miller). Ultimately, Aniston's character was a little too invasive and overbearing as a therapist and a friend so she and Jules parted ways, but it made for a hilarious, heartwarming episode nevertheless.

They've Helped One Another Navigate Divorce

In addition to Aniston's two divorces, Cox split from her husband of nearly 14 years, David Arquette, in 2013. The pair of friends were able to lean on each other during the hard times and be a support system as they each dealt with the ending of relationships, much like how Monica and Rachel were consistently there for one another through countless break-ups on Friends.

RELATED: Every Friends' Couple's First Kiss, Ranked

Aniston told More magazine (mentioned in Hello) back in 2019, "There's absolutely no judgment in Court. You'll never feel scolded. She's extremely fair, ridiculously loyal and fiercely loving. I've slept in her guest bedroom a lot. Without giving away too much of my private stuff, all I can say is she's been there for me through thick and thin."

They Auditioned For Each Other's Friends' Roles

Even though it's difficult to picture anyone but Aniston playing the effortlessly fashionable Rachel Green or anyone but Cox playing the motherly perfectionist Monica Geller, they initially were up for each other's roles early in the audition process.

According to an article by Mental Floss, "The Friends producers originally asked [Courteney] to play Rachel, but she requested the role of Monica because she liked the 'strong' character." Similarly, Aniston first read for the part that eventually went to Cox, but felt more connected to the character of Rachel.

Jen Is The Godmother Of Courteney's Daughter

Cox has been open about her fertility issues during the later seasons of Friends, something that was written into the show in the final season. But while her character was unable to have children, Cox ended up getting pregnant in late 2003 and giving birth to her daughter, Coco Arquette, in June of 2004.

Soon after Coco's birth, the role of godmother was bestowed upon none other than Jennifer Aniston. Us Weekly reported that on Coco's most recent birthday, Aniston took to Instagram to share a picture of her and her goddaughter: "Happy birthday my sweet Cocolicious!'" she captioned an Instagram story to celebrate Coco’s 17th birthday in June 2021 — showing that the longtime bond is stronger than ever.

NEXT: The Funniest Episode From Each Season Of Friends