Looks like there's no rivalry between these celebrity siblings whatsoever!
The model name of Kaia Gerber and her brother Presley, might not sound hugely familiar to you, but her mother's name might ring a few more bells.
While the sister and brother are the new 'It' names of the modelling world in the US, they are largely known as Cindy Crawford's (as in, the supermodel) kids over on this side of the pond.
But today they are making headlines not for their runway swagger but because of the undeniably sweet thing Presley has done for his younger sister.
How much do you love your sister?
Enough to get your name permanently tattooed on your arm? That's exactly what he did.
On Thursday, the male model had 'Kaia XXIII' inked as per the snap below:
Presley posted a picture of the tattoo, written in lowercase script and roman numerals, to Instagram with the caption '23'.
Kaia witnessed her brother's devotion to her first hand and posed for a picture with Presley and his girlfriend, Charlotte, mid-inking.
It looks like these pair are all about strong family values - though Kaia won't be able to return the favour just yet: tattoos are illegal for anyone under the age of 18 in NYC, where Presley got his.
She did, however, speak out about the bond she says with her brother last year. "I love working with him and every time we book a job together I get excited. At first, when we were starting out, we used to shoot a lot together and we would just be there for each other, which is important, especially just starting in such a scary industry — to have someone there that you're comfortable with," she told People.
Can we get an 'Awww!' please?
