Kourtney Kardashian/Instagram

Kourtney Kardashian is celebrating fiancé Travis Barker‘s stepdaughter on her big day.

On Tuesday, the Poosh founder, 42, gave a sweet shout out to Atiana De La Hoya — daughter of Barker’s ex-wife Shanna Moakler and Oscar De La Hoya — in honor of her 23rd birthday.

“Birthday girl❤️,” Kardashian wrote alongside a selfie with Atiana.

She then posted another snap on her Instagram Story of Atiana sitting with two of Kardashian’s kids during a previous snowboarding trip, calling Atiana the “sweetest in all the land.”

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Along with Atiana, Barker is also father to 18-year-old son Landon and 16-year-old daughter Alabama, whom he shares with Moakler. Kardashian shares sons Mason, 12, and Reign, 7, and daughter Penelope, 9, with her ex Scott Disick.

Kardashian and the Blink-182 drummer — who got engaged in October 2021 — have been showing a lot of love to their soon-to-be blended families on social media since their romance began.

Back in December 2021, The Kardashians star shared an Instagram photo posing with Atiana and Alabama. She later posted another family photo, with Landon included, during the holidays.

The previous month, Kardashian and Barker, 46, also made an adorable TikTok video with the reality star’s daughter Penelope.

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Since the couple’s engagement, their children have been more than thrilled for the relationship.

“Congratulations @kourtneykardash and @travisbarker I’m so happy for you guys love you guys so much!” Landon wrote in an Instagram Story in October.

“So happy for you guys I love u both!” Alabama echoed on Instagram at the time before Atiana posted some snaps from the special night, sharing a pic of Kardashian’s new rock as well as an image of the reality TV star and Barker sweetly kissing.