Charlotte Ronson is Dating Fun. Frontman Nate Ruess: Details

Charlotte Ronson and Nate Ruess
Charlotte Ronson and Nate Ruess have been dating for months, sources exclusively tell Us Mike Coppola/Getty Images; Jason LaVeris/FilmMagic

New couple alert! Fashion designer Charlotte Ronson, 36, is dating fun. frontman and songwriter Nate Ruess, 32, multiple sources exclusively confirm to Us Weekly.

The couple, who stepped out for the first time publicly on Saturday, July 19, at the Opening Event of Sound Waves At The Beach at Gurney's Montauk Resort & Seawater Spa, have been keeping their relationship "super hush" for months, one source tells Us

"They've been dating for a few months," a source close to Ronson tells Us. "They're really happy! He is super sweet with her." The source adds the lovebirds met through Charlotte's sister, Samantha Ronson.

PHOTOS: Unlikely couples

An eyewitness tells Us at the event on Saturday, Ruess was "very incognito and didn't want to pose for photos but stood close and held Charlotte's dog Oliver … it's been super hush!" "They were introduced awhile ago and have met a few times but it recently turned romantic," a third source adds. "They have quite a few mutual friends actually. It's cute."

Now that they're official, here's to hoping for an epic double date—Ruess' bandmate Jack Antonoff is dating Girls star Lena Dunham!

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