This Is Us' Alexandra Breckenridge has given birth to a baby girl named Billie, her second child with husband Casey Neil Hooper

Alexandra Breckenridge is thinking pink!

The This Is Us star has welcomed her second child, a daughter, her rep confirms to PEOPLE exclusively.

Billie Breckenridge Hooper was born on Wednesday, Dec. 6, weighing 7 lbs., 13 oz., and measuring 20 inches long.

“We are so excited to have a boy and a girl!” the new mom tells PEOPLE.

Breckenridge, 35, and husband Casey Neil Hooper are already parents to a 15-month-old son named Jack.

“Billie is such a sweet baby girl and Jack is such a social boy, with them only being 15 months apart they will always have a friend to play with,” she adds.

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Courtesy Alexandra Breckenridge
Credit: Courtesy Alexandra Breckenridge
Courtesy Alexandra Breckenridge
Credit: Courtesy Alexandra Breckenridge

Alexandra Breckenridge and newborn daughter Billie

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Breckenridge first announced that she was expecting in August.”We made another one!!” she captioned an Instagram photo of herself resting her hand on her baby bump. “Baby Breckenridge Hooper coming this winter.”

The new addition is the couple’s first daughter, and Breckenridge could not be more excited. “I found out I was having a girl on my birthday,” she told PEOPLE in early November. “My doctor called and I said, ‘This is the best birthday present ever!’ I really wanted to have a girl.”

Breckenridge added that she even splurged on her little one’s wardrobe in preparation. “I’m trying to stop myself — there are so many cute girl clothes!” she admitted.

Palmer's Celebrity "Spokes-belly" Shoot with Alexandra Breckenri
Alexandra Breckenridge

Alexandra Breckenridge

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The news of her daughter on the way created speculation from This Is Us fans this summer because Breckenridge was pregnant while filming season 2. But viewers should not expect her character Sophie — Kevin Pearson’s ex-wife and rekindled love interest — to become pregnant in the show.

Breckenridge previously shared how she hid her baby bump during filming. “They have tricks and different clothes to hide stuff, and you can stand behind a counter and frame halfway up,” Breckenridge explained during PEOPLE’s This Is Us season 2 premiere party and screening.

“It hasn’t been too bad,” continued The Walking Dead alum. “They can also digitize it out these days!”