Jennifer Aniston Celebrates Courteney Cox on Her 60th Birthday: ‘Fiercely Loyal to the End’

"I can’t imagine a world without her. It’s one of my great honors to call her one of my best friends for life," Aniston said of her former 'Friends' costar

Jennifer Aniston is celebrating her friend Courteney Cox's milestone birthday!

Cox turned 60 on Saturday, June 15, and in honor of the occasion, her Friends costar posted a sweet tribute to her on Instagram.

"Celebrating this powerful, magical, mystical, interesting, interested, ferociously talented girl today!!! My sweet CC @courteneycoxofficial," Aniston, 55, began the caption of the post, featuring a carousel of photos of the pair together through the years.

The carousel kicked off with a throwback photo of the pair with Cox's daughter, Coco, 20, when she was younger, sleeping between them. It also featured a still of the two actresses on Friends and a screenshot of a video call.

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"She’s funny like no other, STUNNING on the inside and out. Independent in the most gorgeous way, cares for everyone even if she doesn’t know you," Aniston's caption continued. "Terrified of dogs even though I’ve never known her NOT to have at least two of them ☺️. Fiercely loyal to the end."

The Morning Show star went on to praise Cox's talent for interior design and her ability to spot "a smudge on a window" from a mile away.

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"She doesn’t care what other people think!! 👏🏼👏🏼 I can’t imagine a world without her," Aniston concluded the heartfelt tribute. "It’s one of my great honors to call her one of my best friends for life… Happy happy birthday CC. I love you! ❤️."

The duo's decades-long friendship began on their iconic sitcom and has stayed strong through the years. They recently enjoyed a girls' night out together in Los Angeles in April.

Related: Jennifer Aniston and Courteney Cox Celebrate Lisa Kudrow on Her 60th Birthday: ‘Cherish You’

When Aniston turned 55 in February, Cox posted a tribute to her friend on social media.

“Happy Birthday my sweet Jenny Louise. Also don’t know why I call her that...but I sure do love you ♥️," the Cougar Town star wrote of Aniston at the time.

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