Ashlee Simpson and Evan Ross
Ashlee Simpson and Evan Ross have welcomed their first child.Getty

Congratulations are in order for Hollywood power couple Ashlee Simpson and Evan Ross, who welcomed their first child together.

E! News reports that The Hunger Games: Mockingjay -- Part 1 star, who is the son of legendary singer Diana Ross, and his singer wife are the proud parents of a baby girl.

"Their whole family was around to support them," a source told the publication. "Evan was very emotional and loves Ashlee so much. He did not leave her side and wanted to go through this with her every step of the way."

The child's name and other details are not yet known.

In January 2014, Ross and Simpson stunned fans when they announced their engagement following a whirlwind romance. Eight months later, the couple exchanged vows at Diana Ross' Greenwich, Connecticut estate in a romantic Bohemian-style ceremony officiated by his superstar mother.

And, according to the insider, Ross is over the moon about becoming a first time father. "He can't wait to be a dad. He would do anything for Ashlee and now this baby girl," the source added. "Ashlee is doing great and can't wait to get home to be with her family."

Although Simpson never made an official announcement, news broke of her pregnancy in December 2014 just weeks after Ross hinted that he wanted to start a family.

"I would love to [have kids]. As many as possible," he told Us Weekly at The Hunger Games: Mockingjay premiere, adding: "I've been with her now for a while so it just feels right. I'm happy to say she's my wife. It's the best thing ever."

The new addition joins six-year-old Bronx Mowgli, Simpson's son from her first marriage to rocker Pete Wentz.