Hugh Hefner’s son Cooper is officially off the market.

Cooper and “Harry Potter” actress Scarlett Byrne legally married in Ventura, Calif., at the County Clerk’s Office on Monday.

“Scarlett and I have made it officially legal and the two of us could not be happier,” Hefner, 28, wrote on Twitter, announcing the news. “Cheers to a life full of love, happiness, adventure, and great purpose, Mrs. Hefner.”

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The couple are now planning a big wedding celebration in the coming months for friends and family.

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“I love you Cooper,” the 29-year-old “Vampire Diaries” actress wrote on Instagram along a pic of them at the clerk’s office. “I am proud to stand by your side, as your partner, your friend, and your wife. I cannot wait to continue building a life together. My heart is so full and I am so grateful for our love.”

The longtime couple announced their engagement in August 2015.

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Cooper is one of Hugh’s four children. His mother, Kimberley Conrad, was married from 1989 to 2010 to the late Playboy founder, who died in 2017. In April 2019, Cooper left the his father’s company to launch his own media brand.

This article originally appeared in Page Six