Robin Tunney Welcomes Daughter Colette Kathleen: She's 'Ready to Take Over the World'

New year, new baby!

Robin Tunney announced on Thursday that she has welcomed her second child, daughter Colette Kathleen.

“We are thrilled to introduce you to Colette Kathleen. Oscar is now a big brother,” The Mentalist star, 47, wrote alongside an adorable clip that showed her 3½-year-old son Oscar Holly doting on his sibling.

“I gave birth January 8th and our hearts have gotten bigger whilst our rest has shrunken considerably,” she added. “This firecracker came out with a thick head of strawberry blonde hair, ready to take over the world. #newborn #babygirl.”

In the heartwarming video, Tunney, who did not previously reveal on social media that she was expecting another child, can be heard asking her son if he wants “to sing” a song for his sister, before he launches into a rendition of “Rock-a-Bye-Baby.”

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View this post on Instagram We are thrilled to introduce you to Colette Kathleen. Oscar is now a big brother. I gave birth January 8th and our hearts have gotten bigger whilst our rest has shrunken considerably. This firecracker came out with a thick head of strawberry blonde hair, ready to take over the world. #newborn #babygirl

A post shared by Robin Tunney (@robintunney) on Jan 23, 2020 at 10:14am PST

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View this post on Instagram I’m going to keep on posting pictures of Oscar until he’s old enough to tell me to stop because he finds me embarrassing.

A post shared by Robin Tunney (@robintunney) on Aug 8, 2019 at 10:58pm PDT

//www.instagram.com/embed.js

 

The actress and her longtime partner Nicky Marmet welcomed their first child in June 2016.

“My greatest work, Oscar Holly Marmet,” Tunney wrote on Instagram after her son’s arrival, next to a photo of her then-newborn snoozing in a basket.

Much like with her second child, Tunney’s pregnancy came as a surprise to fans.

“Sorry I didn’t talk about being pregnant. Wanted to keep it all for myself,” she added, including the hashtags “#momlife,” “#bestbaby” and “#soinlove.”

View this post on Instagram We’re the people that i made fun of before I had children. I love you @shiriappleby #milkandcookies #halloweencostume

A post shared by Robin Tunney (@robintunney) on Oct 31, 2019 at 9:10pm PDT

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In May 2019, less than nine months before welcoming her daughter, Tunney reflected on the joys and struggles that come with being a new mom, as she shared that she missed having a newborn around.

“I took this selfie after I had Oscar because I thought I couldn’t possible look as tired as I felt. I couldn’t believe it was me!!!!” she wrote.

“Every mother is a ninja warrior for what they are able to pull off. Congrats to all of the you out there, you’re miraculous. #womenareamazing I miss mine!” she added.