Legends actress Ali Larter has been holding onto a precious announcement for the past week: she has finally given birth to her beautiful baby girl!

Larter posted the announcement on her website on January 19^th, along with a photo of her little girl. In the picture, the child is fast asleep, wrapped in whit blankets on a soft, fur skin blanket. That is almost too adorable to be true! This is Larter's second child with Hayes MacArthur, the actress's husband.

So who is this mystery baby? Ali couldn't wait to release the name on her website, AliLarter.com. "It's a girl! We couldn't be more excited to share news of the arrival of Vivienne Margaret MacArthur on Thursday January 15th 2015," Larter wrote. "7.5 lbs of love." Vivienne Margaret MacArthur is following in her parents' footsteps, already receiving boundless love and support from adoring fans.

Vivienne's older brother, 4-year-old Theodore, hasn't expressed any great enthusiasm over his newborn sister, but Vivienne and her parents couldn't stop themselves from offering him a little treat. "She came bearing gifts for her brother: Batman sheets and lots of Gummy Bears!!!" Larter wrote on the website.

Larter revealed she was expecting in an August appearance on The Tonight Show with Jimmy Fallon, when she stood up to show off her baby bump. Larter and MacArthur have been married for almost six years, and they both remained in acting despite their growing family. Ali's show Legends will be entering its second season, and Hayes will be appearing on the TBS comedy Angie Tribeca.