Cara Delevingne and Kaia Gerber have matching 'Solemate' feet tattoos.

The best friends have shown their love for each other by getting the ink tributes.

To mark Cara's 28th birthday on Wednesday (12.08.20), Kaia shared a series of feet selfies with her ''Solemate'' on her Instagram Stories.

She captioned one shot of the pair foot-to-foot: ''Happy birthday to my solemate.''

And alongside another snap of the pals at a Black Lives Matter protest in Los Angeles in July, the 18-year-old model hailed the 'Carnival Row' actress ''the best protest buddy.''

Cara has been spending lots of time with Kaia and her girl pals Margaret Qualley and her sister Rainey Qualley amid the coronavirus pandemic and following her split from Ashley Benson in April.

The actress-and-model called time on her romance with the 'Pretty Little Liars' star after almost two years of dating.

A source claimed at the time: ''Cara and Ashley always had their ups and down before but it's over now. Their relationship just ran its course.''

Cara was first spotted with the 30-year-old actress in August 2018, when they were photographed kissing at London's Heathrow Airport.

The 'Paper Towns' actress confirmed their relationship in June 2019, when she revealed her motives behind sharing an Instagram video of herself kissing Ashley.

She said at the time: ''I don't know because it is Pride, it's been 50 years since Stonewall happened and I don't know. It's been just about our one-year anniversary so, why not?''

Meanwhile, the 'Her Smell' star is asking her fans to sign a petition for her birthday, which urges Congress to pass the Break Free From Pollution Act, which calls for the planet and public health to be made a priority.

Alongside devastating pictures of oceans overflowing with junk and a turtle stuck in plastic, Cara wrote on Instagram: ''For my birthday this year, join me in demanding Congress pass the Break Free From Pollution Act and put our planet and public health above corporate profit.

''Link in my bio to sign the petition - can we get 28,000 signatures for my 28th birthday? @sierraclub (sic)''