The 25-year-old is dating Olivier Sarkozy who is the half brother of former French President, Nicolas Sarkozy.
The loved up twosome flaunted their romance at Madison Square Gardens last month as they watched the New York Knicks play the Los Angeles Clippers.
The former child star turned fashion mogul snuggled into the French asset manager and he’s seen stroking her hair and whispering into her ear without a care for who saw them.
Mary-Kate and Olivier have apparently been dating for a month and spent Memorial Day weekend together in the Hamptons.
He had previously dated actress Stella Schnabel and the New York Post reports that Olivier has been told to “tone it down and curb his high-profile lifestyle by his bosses” at global asset management company, Carlyle.
Olivier has been married before and has two children. The blonde fashionista was with New York artist Nate Lowman between 2008 and 2010. She also dated Greek shipping heir Stavros Niarchos.