Nate Ruess and girlfriend Charlotte Ronson welcome first child

Mike Pont/WireImageCongrats to Nate Ruess and girlfriend Charlotte Ronson: the fun. frontman and the English fashion designer have welcomed their first child, a baby boy named Levon, PEOPLE has confirmed.

Ronson's mother, Ann Dexter-Jones, posted a photo of herself and her grandchild on Instagram. "#iamsoinlove with my very first #newborn beautiful #grandchild," she wrote in the caption.

The New York Post's Page Six reports that Ruess and Ronson have been dating since 2014. Ronson's brother is Grammy-winning DJ, producer and artist Mark Ronson, and her sister is Samantha Ronson, a deejay and singer/songwriter who's currently a member of the band Ocean Park Standoff.   

Ruess released his debut solo album Grand Romantic in 2015.

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