Mary-Kate Olsen Mary-Kate Olsen

Child star-turned-clothing designer Mary-Kate Olsen is reportedly "head over heels" for Olivier Sarkozy, the half-brother of former French president Nicolas Sarkozy, according to The NY Post.

Olsen, 25, and Sarkozy, 42, were spotted together in the Hamptons over the holiday weekend.

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Sarkozy is the managing director of the Carlyle Group, an asset-management firm. He previously dated actress Stella Schnabel. Olsen, who rose to fame on Full House with her twin sister Ashley before the pair launched their own lucrative brand, dated artist Nate Lowman for two years, but the couple split in 2010.