Mischa Barton has reportedly got engaged to Kimberly Stewart's ex-fiancé, Cisco Adler.The beautiful actress accepted 26-year-old Adler's proposal after he got down on one knee in Hawaii. The Whitestarr singer - who was engaged to rocker Rod Stewart's daughter Kimberly last year - popped the question to Mischa while presenting her with a giant bunch of tropical flowers, according to Britain's Daily Star newspaper. The 19-year-old has happily accepted.Meanwhile, 'The OC' star was told to have sex with Leonardo DiCaprio to boost her career - but didn't because he was too old.Mischa claims she was urged by her publicist, Craig Schneider, to bed the Hollywood heartthrob to give her more publicity.She confessed when she and Craig spotted the 'Titanic' star, who recently split from Brazilian supermodel Gisele Bundchen, at a photoshoot in Malibu, he turned to her and said: "For the sake of your career, go and sleep with that man"But the sexy star said she was put off dating DiCaprio because he is ten years older than her and she isn't interested in dating older men. She said: "Isn't Leo like, 30, or something?"