Even Olivier Sarkozy's ex-wife is a fan of Mary-Kate Olsen!

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In the new issue of Us Weekly (on stands Friday), a source says the fashion designer, 26, has won over her boyfriend of seven months' former spouse. "Mary-Kate always includes her," a source says of Charlotte Sarkozy, 42, who split with the French financier in 2010 after 13 years of marriage.

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"MK asks her permission about things that concern the kids [Julien, 11, and Margot, 9]," the source adds. "So Charlotte loves her!"

Olsen and her boyfriend, 42 -- the managing director of the Carlyle Group's global financial services division and half-brother of the former president of France, Nicolas Sarkozy -- currently live in a $6.25 million East Village townhouse. "They are madly in love," an insider previously told Us.

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Ashley Olsen's famous twin sister has said little about their May-December romance, though she did tell WSJ. Magazine she doesn't pay attention to doubters. "Everyone has an opinion," Olsen said of their 16-year age difference. "I find it's better to focus on what's in front of you and to keep putting one foot in front of the other."

This article originally appeared on Usmagazine.com: Olivier Sarkozy's Ex-Wife "Loves" His Younger Girlfriend Mary-Kate Olsen!