Nothing says you love your sister more than getting her name tattooed on your body.

Presley Gerber visited Bang Bang Tattoos in New York City on Thursday where he got “Kaia XXIII” inked on his left tricep as shared on Instagram. The 18-year-old older brother of model-of-the-moment Kaia Gerber enlisted famed tattoo artist Jon Boy, who’s inked plenty of stars like Kendall Jenner, Hailey Baldwin, Bella Hadid and Ashley Graham, to write the lowercase script and roman numerals.

In fact, Kaia, 16, witnessed her sibling get the permanent name dedication. Also in attendance was Presley’s girlfriend Charlotte D’Alessio, 19, who shared a photo of him in the process of getting tattooed.

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Kaia and Presley’s famous parents, Cindy Crawford and Rande Gerber, even chimed in on their son’s new body art.

“RG + JG APPROVED!” the proud dad wrote in the comments section of Presley’s Instagram while the famed supermodel simply wrote: “Cool.”

While Kaia didn’t get her brother’s name tattooed, it’s obvious how close their sibling relationship is.

For the pair, working in the same industry means that they get to spend a lot of extra quality time together, which explains why they’re always posing together on social media. But aside from being able to have fun on set, they’re able to act as each others’ support systems along the way.

“I love working with him and every time we book a job together I get excited,” she told PEOPLE in May. “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.”

In addition, Kaia and Presley joined the Calvin Klein family in January to front the brand’s Spring 2018 denim campaign.