Hugh Hefner's Christmas was extra, extra jolly this year: He's engaged again! The Playboy founder, 84, is engaged to Crystal Harris, his 24-year-old girlfriend and Playmate, a Playboy rep confirms to UsMagazine.com. PHOTOS: See Hugh and Crystal's Christmas card! Hefner first Tweeted about it on Sunday. "When I gave Crystal the ring, she burst into tears," the Girls Next Door star wrote. "This is the happiest Christmas weekend in memory...I got what I was hoping for for Christmas...Crystal's love." PHOTOS: The year's biggest engagements To make his news absolutely clear, the mogul then added: "Yes, the ring I gave Crystal is an engagement ring. I didn't mean to make a mystery out of it. A very merry Christmas to all." PHOTOS: Can you believe these couples' age differences? It will be the third marriage for famous bachelor Hefner. He wed first wife Mildred in 1949 (they have grown children Christie, 58, and David, 55) before divorcing in 1959. In 1989, he walked down the aisle with Playmate of the Year Kimberley Conrad, and they went on to have sons Marston, 10, and Cooper, 9. The duo's divorce was finalized last year