Amelia Hamlin Gifts 'Birthday Cutie' Scott Disick a Harley Davidson at Party with Kardashians

Amelia Hamlin celebrated boyfriend Scott Disick's 38th birthday in a big way — and she did so alongside the Kardashian family.

Disick, whose actual birthday falls on Wednesday, showed off the Harley Davidson motorcycle that his 19-year-old girlfriend gifted him on his Instagram Story Monday. "New Harley, can't complain," he captioned one video, adding, "Thanks @ameliagray."

Documenting the festivities on her own Instagram Story, Hamlin posted a photo of Disick's birthday cake, which read: "Disick Aviation. Happy Birthday." She also flashed a diamond bracelet from Luxe VVS Jewelers — a celebrity jewelry company that provided jewelry as party favors to the attendees.

Hamlin also uploaded a video of "birthday cutie" Disick kissing her on the cheek.

Many of the Kardashian-Jenner family members were also in attendance. Kim Kardashian West, for one, shared a photo on her Instagram Story of large silver balloons that spelled out "Happy Birthday Lord." The Skims mogul, 40, also documented the onsite Raising Cane's Chicken Fingers and Churro Man food trucks.

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She also captured Disick showing off his jewelry party favors. "This is how the Lord does it," he said. "I'm sorry that everybody else gives out candy. I give out ice."

Khloé Kardashian shared multiple videos of herself on her Instagram Story wearing a necklace she received at the celebration, as well as a look at the giant silver balloons and Disick's birthday cake. Kris Jenner, meanwhile, noted what a "great party favor" the jewelry was in her own Instagram Story video.

Additionally, Disick's ex Kourtney Kardashian shared a video of herself hanging out with Sia at the party.

Disick — who shares Mason, 11, Penelope, 8, and Reign, 6, with Kourtney, 41 — has been linked to Hamlin since lasta October. After the two made things Instagram official around Valentine's Day, a source told PEOPLE in March that their relationship was "getting serious."

"He's been telling friends how much she means to him and how into her he is," the source said, noting that they don't "feel" their 18-year age gap.

Not only has Hamlin spent time around Disick's family, but the model's mother, Lisa Rinna, recently revealed that she and husband Harry Hamlin have also met Disick. "[He's] very similar to what you thought when you met him," Rinna, 57, told Andy Cohen on Watch What Happens Live earlier this month. "He's more handsome in person. He was very nice, we had a very nice time."

The Real Housewives of Beverly Hills star added, "It is what it is, guys. It is what it is."