On Wednesday, Disick purchased yet another lavish gift for his model girlfriend: a signed Helmut Newton print worth $57,500, PEOPLE confirms.
Considered one of the photographer's most provocative pieces, the photo, titled "Saddle II," depicts a model clad in tights and a blazer as she straddles a saddle resting atop an armchair. The black-and-white piece was originally shot for a 1976 edition of Paris' Vogue Hommes magazine.
To make the gift even more memorable, Disick bought the vintage print from the ArtLife Gallery's pop-up in Miami's design district using EthereumPay's $EPAY Cryptocurrency.
Hamlin rang in her milestone birthday in Miami over the weekend, sharing an array of posts on her Instagram Story highlighting her lavish celebrations.
First sharing a video of her outfit for the night - a metallic gold crop top with a matching miniskirt - Hamlin then shared more posts from the evening out, including a shot of her holding Disick's hand.
She also shared videos of her birthday dinner at the Papi Steak restaurant, which presented the model with a glittery cake adorned with pictures of herself.
In another video shared by Hamlin, Disick gifted his girlfriend a cross necklace by placing it around her neck, which prompted Hamlin to tear up and then thank Disick with a kiss on the lips.
In other posts, Hamlin is seen celebrating her birthday with a stop at LIV nightclub in the Florida city.
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In May, Hamlin showered Disick with his own birthday love when the reality star turned 38. The model shared several photos of the couple, including a snap of 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.
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Back in March, a source told PEOPLE that the relationship between the Keeping Up with the Kardashians star and the model - who is the youngest daughter of Lisa Rinna and Harry Hamlin - was "getting serious."
"He's been telling friends how much she means to him and how into her he is," said the source.
As for their years-wide age gap, the source said that the couple doesn't "feel" the decades between them. "She grew up in the industry and knows how all this works," the source added about Hamlin. "It's a different type of maturity, and they really don't feel the age difference."