The little girl is the 33-year-old actress’ first child with long-term partner Hayden Christensen.
'She's wanted to have a baby for a long time and is going to be an amazing mom'
While the name is somewhat unusual, it appears the couple took inspiration from Disney tale Sleeping Beauty.
When the three fairies try to hide Aurora from the Evil Queen Maleficent, they give her the moniker Briar Rose.
Rachel and Hayden have been dating since 2007. The pair met on the set of movie Jumper and got engaged in 2008. They briefly split in 2010, but confirmed they were dating again a few months later.
Upon the pregnancy news being confirmed earlier this year, a source close to the couple revealed that former O.C. star Rachel was more than a little excited about becoming a mother.
"She's wanted [to have a baby] for a long time and is going to be an amazing mom. Everyone is ecstatic for her," the insider told Us Weekly.
One person who publicly shared her delight at Rachel's pregnancy earlier this year is her Hart of Dixie co-star Jaime King.
"Her best friend has a kid and she has a lot of friends with children, so I'm just there to support her however I can and honour and respect her processes," Jaime, 35, previously said. "She loves James, she's always bringing him toys. Just seeing her with my son, I know she's going to be the best mother."
Rachel has made it no secret that she is keen to become a mom. In an interview conducted with Cosmopolitan magazine in May 2013 the brunette beauty gushed about the thought of having children of her own.
"I definitely have family on the brain. Having kids is something I want to see in my future – I hope,” she smiled at the time.
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