Amelia Hamlin Posts Birthday Tribute to Her 'Special Person' Scott Disick: 'I Love You'

Amelia Hamlin is celebrating boyfriend Scott Disick's 38th birthday with a sweet Instagram tribute.

The model, 19, shared several photos on Instagram Wednesday to mark Disick's latest year around the sun.

The pictures included the pair on a boat together, holding hands and tanning.

"Happy birthday my love. you light up my life, and make my world better. i can't imagine what i would do without you," Hamlin wrote in the caption to Disick, to whom she's been linked since October of last year. The two later made things Instagram official around Valentine's Day.

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

Amelia Hamlin/instagram

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

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

The 19-year-old model continued, "Thank you for being you. the most caring, loving, special person on this planet. i'm so lucky. i'm so blessed to have met you."

"I love you 🥺," Hamlin added.

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

On Monday, Hamlin – who appeared on Real Housewives of Beverly Hills with her parents Lisa Rinna and Harry Hamlin – celebrated Disick's birthday alongside the Kardashian family. Disick shares kids Mason, 11, Penelope, 8, and Reign, 6, with ex Kourtney Kardashian.

At the party, the model gifted her boyfriend a Harley Davidson motorcycle. "New Harley, can't complain," he captioned one video shared to his Instagram Story, adding, "Thanks @ameliagray."

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

Amelia Hamlin/instagram Amelia Hamlin and Scott Disick

RELATED: Lisa Rinna Says Daughter Amelia Hamlin's Relationship with Scott Disick 'Is What It Is'

In March, a source told PEOPLE 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.

Hamlin's parents have met Disick, Rinna, 57, revealed on a recent appearance on Watch What Happens Live, where she opened up about her daughter's relationship with the Keeping Up with the Kardashians star.

RELATED VIDEO: Scott Disick Gave Out Diamond Jewelry and Rolex Watches as Party Favors at His 38th Birthday Bash

When asked by host Andy Cohen what her "first reaction" was to learning that Hamlin was dating Disick, the reality star initially shied away from the question. "Uh, yeah," she said, laughing.

As Cohen, 52, dug deeper, he then asked Rinna if she had been in contact Kardashian's mother Kris Jenner to talk about the romance.

"I have not," Rinna answered, before adding, "I have met him now."

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"He was very nice, we had a very nice time," Rinna continued.

She added of the relationship: "It is what it is, guys. It is what it is."