Ashlee Simpson and her husband Evan Ross have welcomed their first child together, a baby girl Credit: Axelle/Bauer-Griffin/FilmMagic

Get ready, Bronx! Ashlee Simpson and Evan Ross have welcomed their first child together, a source confirms to Us Weekly. The couple's baby girl arrived on Thursday, July 30.

Us confirmed in February that Simpson, 30, and the Skate God actor, 26, were expecting. Jessica Simpson's younger sister already shares son Bronx, 6, with ex-husband Pete Wentz.

"I told him pretty early on," Simpson said of her baby boy at the time. "He wanted to have a sister, so he’s really excited! He’s got a little brother. Now he’s going to have a little sister!"

Simpson and Ross married at his mom Diana Ross' lavish Greenwich, Conn., estate last August. (Fall Out Boy rocker Wentz welcomed baby boy Saint Lazslo with girlfriend Meagan Camper that same month.) Bronx walked his famous mom down the aisle, followed by Jessica and husband Eric Johnson's daughter Maxwell, 3, and son Ace, 22 months, as the flower girl and ring bearer.

Simpson was often photographed hitting the gym with Ross during her pregnancy, and particularly liked taking Tracy Anderson's classes. "I'm feeling great," she told Us at the Just Before I Go Hollywood premiere in April. Ross added: "She has to be the best pregnant mom in the world. Everybody talks about how hard it is but she is so easy and enjoys it and smiles all the time."

In June, the star was the guest of honor at an outdoor baby shower, hosted by Jessica and attended by actress Odette Annable. The dad-to-be, meanwhile, had a guys' day out with Johnson and his pals at The Beverly Hills Hotel.

E! was first to break the baby news.

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