Kaia Gerber has issued some guidance for her elder brother Presley Gerber about taking care of his skin in the sun.

Presley, 24, and Kaia, 21, are the children of model Cindy Crawford and Rande Gerber, a businessman.

Both siblings followed in their mother’s footsteps and have successful modelling careers, often sharing their work and off-duty looks on social media.

On Saturday (19 August), Presley shared photos of himself on a sandy beach while topless. The images show him with a bandana draped around his shoulders.

In the caption to the Instagram post, Presley wrote: “Sunscreen’s a myth”.

In fact, sun protection provides an essential barrier to harmful UVA and UVB rays. According to the American Cancer Society, UVB rays are responsible for the majority of cases of skin cancer.

In disagreement with her brother’s statement, Kaia left a public comment on the post to give him some alternative guidance.

“Hi Presley! It’s me, your sister!” she began her message.

“Remember me from childhood? We share the same parents [wacky face emoji] I actually wanted to share with you that sunscreen is not a myth!! It is real!! I actually use it myself!!”

Fans and followers have jumped in on their exchange, with many leaving laughing emojis at the humorous tone of Kaia’s message.

“Absolutely! Sharing is caring @presleygerber!” one fan remarked. “Sis has got your back! You’ve raised them well @cindycrawford!”

Another simply wrote: “Love your brain Kaia!!”

Earlier this year, Kaia shared her thoughts on the “nepo baby” debate, which highlights the privilege enjoyed by those in the entertainment and creative industries who have famous parents.

Speaking to Elle in January, the model and actor acknowledged the ways that nepotism had helped her career.

“I won’t deny the privilege that I have,” she said. “Even if it’s just the fact that I have a really great source of information and someone to give me great advice, that alone I feel very fortunate for.”

She also shared a comment that Crawford made about her daughter’s busy modelling career.

“My mom always joked, ‘If I could call and book a Chanel campaign, it would be for me and not you,’” Gerber added. “But I also have met amazing people through my mom whom I now get to work with.”