Cara Delevingne and Kaia Gerber Have Matching Tattoos Celebrating Being 'Solemates'

Happy birthday, Cara Delevingne!

Delevingne rang in her 28th birthday on Wednesday, and her friend and fellow supermodel Kaia Gerber wished her a happy day on Instagram — revealing they have matching tattoos on their feet.

"Happy birthday to my solemate @caradelevingne," Gerber, 18, wrote atop a photo of the friends hugging feet.

Sharing several more photos of the Carnival Row actress, Gerber shared some more tributes, writing, "the only person who wears my face on a sweatshirt," and "the best protest buddy," and atop a video of the duo dancing, "coolest guys at the function."

Included in the photos was a snapshot of the models' feet, showing tattoos of the word "solemate" along each woman's arch of her foot.

Delevingne and Gerber recently donned an oversized cable sweater in celebration of Taylor Swift's eighth studio album, Folklore.

"@taylorswift we love our CARDIGAN," Gerber wrote alongside a mirror selfie of the pals, referring to the first single from the album.

Gerber wasn't the only star to wish Delevingne a happy birthday.

Margaret Qualley shared a series of silly photos of the Suicide Squad actress to mark the milestone.

"Dear @caradelevingne, man, too much to say. So incredibly lucky to have you as a friend. I love you, happy birthday!" the Once Upon A Time... in Hollywood actress wrote in an Instagram post.

Delevingne split with longtime girlfriend Ashley Benson in early April, sources confirmed to PEOPLE in May.

"Cara and Ashley always had their ups and downs before, but it's over now," the source told PEOPLE at the time. "Their relationship just ran its course.”

A source added at the time that Delevingne had been spending time with friends while social distancing amid the coronavirus pandemic, including Gerber, Margaret and the actress' sister Rainey Qualley.