Nicolas Sarkozy’s brother Olivier Sarkozy has moved on from Stella Schnabel and is now dating Mary-Kate Olsen. Sources say the former French president’s 42-year-old younger half-brother, who’s managing director of the Carlyle Group, has been seeing 25-year-old Olsen for about a month, and they’re “head over heels” for one another. The couple was spotted in the Hamptons over Memorial Day weekend. Olsen dated artist Nate Lowman for two years until splitting in 2010. Divorced Olivier dated Schnabel for more than a year before they parted in March. Neither Sarkozy nor a rep for Olsen responded to us.