The 38-year-old Legends actress shared the first photo of her daughter, as well as the baby name on her website. Larter made sure to include her son, 4-year-old Theodore (or Teddy, as they like to call him), in the sweet announcement.
"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," she wrote, sharing a photo of her daughter wrapped in a blanket and sleeping sweetly.
"She came bearing gifts for her brother: Batman sheets and lots of Gummy Bears!!! 7.5 lbs of love," she gushed.
Vivienne is a beautiful name of French origin that means "lively." According to the Social Security Administration, this name first became popular in 1914; however, it dropped off the top 1000 popular baby name charts after 1930 and didn't become popular again until 2009, when it was ranked at number 531. This name continues to climb the charts and is currently ranked at 280. Sophia is the most popular name this year.
Larter isn't the only celebrity to pick this name, as Angelina Jolie and Brad Pitt picked this name for their daughter, Vivienne Marcheline. NFL star Eric Decker and Jessie James chose the same name with a slightly different spelling (Vivianne), as did Gisele Bundchen and Tom Brady (Vivian).
Her middle name of Margaret is of Irish origin that means "name of a saint." This name peaked in the early 1900s; however, it has stayed on the top 1000 baby name list which proves this American classic name is here to stay. Margaret is becoming a popular middle name choice for many celebrities, with stars like Nicole Kidman (and her daughter Faith Margaret), Mark Wahlberg (daughter Grace Margaret) and Tori Spelling (daughter Hattie Margaret) all choosing this middle name.
The Heroes alum, who showed off her baby bump on her Instagram page, revealed they were not finding out the sex of the baby until delivery.
"We're not going to find out," Larter told Us Weekly. "It'll be a surprise."
Tell us: What do you think of the name Vivienne Margaret?
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