Mandy Moore Gives Birth to 3rd Child with Husband Taylor Goldsmith: 'Our Very Own Big Three'

Mandy Moore officially has her "Big Three"!

The This Is Us alum gave birth to her third child, a baby girl, with husband Taylor Goldsmith , announcing the news on Wednesday, Sept. 25 on Instagram.

Moore, 40, also shared the official moniker of her newest family member, introducing her followers to Louise Everett Goldsmith with a sweet black-and-white photo from the hospital room shortly after giving birth.

Check out Moore's first photo of baby Louise here !

The new babe joins Moore and Goldsmith's family as their first daughter, joining big brothers August "Gus" Harrison , 3, and Oscar "Ozzie" Bennett , who turns 2 years old next month.

The actress wrote alongside the photo, "Lou is here! Louise Everett Goldsmith arrived happy, healthy, expeditiously and right in time for Virgo season. She is our absolute dream girl and her big brothers are already as obsessed with her as we are."

"Endlessly grateful for our family of 5 (and our very own big three) and soaking in every moment of this special time. 💓💓💓," Moore concluded.

Moore first announced the news of her third pregnancy in May, sharing a photo of Gus and Ozzie wearing matching T-shirts that read "Big" and "Middle," respectively.

"Sometimes life imitates art. The third in our own Big Three coming soon," Moore wrote at the time , referencing her work in the series This Is Us , where she played a mom to three kids, affectionately nicknamed the "big three" by their father, played by Milo Ventimiglia .

Just like Moore's real life, her character was a mom to two sons ( Sterling K. Brown ) and ( Justin Hartley ), plus one girl, played by Chrissy Metz .

"Can’t wait for these boys to have a baby sister. 💓💓💓," the actress added in her May 31 post about her real-life trio.

After sharing the news of Louise's birth, many of Moore and Goldsmith's celebrity pals took to the comments on Instagram to offer their congratulations, including messages from Minka Kelly , Bryan Greenberg and Amanda Kloots .

Jamie Otis from Married at First Sight , who just welcomed twin boys with her husband, Doug Hehner , also left a comment that read, "Congratulations mama!❤️ so much joy All over your face! I hope the recovery is smooth for you!🙏 Yay to your real-life big 3!"

Congratulations to the new family of five!

Next: Get to Know Mandy Moore's Husband and Baby Daddy Taylor Goldsmith