Courteney Cox celebrates daughter Coco's 18th birthday: 'I'm so proud to be your mom'

Courteney Cox's daughter Coco Arquette is all grown up and making her mom proud.

The "Friends" alum took to Instagram on Monday to celebrate Coco's 18th birthday, sharing a sweet selfie of the two together at the beach, as well as two other photos from her daughter's childhood.

"Happy 18th birthday coco! I'm so proud to be your mom," Cox, who turns 58 on Wednesday, wrote. "You are courageous, smart, deep, funny, unique and beautiful with the biggest heart. I can't wait to see what's next. I love you x."

Celebrities like Kate Hudson and Octavia Spencer also chimed in, wishing Coco well in the comments.

David Arquette, Coco's father, shared a video of her singing onstage to Instagram on Tuesday, to mark her life milestone. He noted in the comments that he had originally posted the video the day prior, but it had "disappeared."

"Happy 18th Birthday Coco!!! I can't begin to express how proud I am to be your father and the joy you have brought into my life," he wrote in the caption. "I love you!"

Cox and Arquette were married from 1999 to 2013. While Coco is Cox's only child, Arquette also shares two children with wife Christina McLarty: sons Charlie, 8, and Augustus, 5.