Kaitlynn Carter Welcomes Second Baby with Boyfriend Kristopher Brock

NEWPORT BEACH, CALIFORNIA - SEPTEMBER 17: Kaitlynn Carterattends Fashion Island's StyleWeekOC In Partnership With SIMPLY – Day Two at Fashion Island on September 17, 2022 in Newport Beach, California. (Photo by Jon Kopaloff/Getty Images for Fashion Island)
NEWPORT BEACH, CALIFORNIA - SEPTEMBER 17: Kaitlynn Carterattends Fashion Island's StyleWeekOC In Partnership With SIMPLY – Day Two at Fashion Island on September 17, 2022 in Newport Beach, California. (Photo by Jon Kopaloff/Getty Images for Fashion Island)

Jon Kopaloff/Getty for Fashion Island

Kaitlynn Carter has added a new addition to her family.

The Hills: New Beginnings star, 34, announced on Instagram Friday that she gave birth to her second baby, a daughter, with boyfriend Kristopher Brock.

Sharing a collage of photos of the pair with their newborn at the hospital, the couple also included a black and white photo of Brock holding their daughter in his arms, as well as a few shots of Carter holding her baby girl in her hospital bed.

"… and then there were 5… 🤍," Carter captioned the post. Their daughter, whose name has not yet been revealed, joins siblings Rowan Carter, 17 months, and Brock's 6-year-old child from a previous relationship.

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Carter and Brock revealed in October that they were expanding their family with a joint post shared on Instagram.

In it, the couple posed for a mirror selfie, with Brock holding the camera up to his eye as he sat on his bed, photographing Carter with her baby bump on full display in front of him.

"Baby girl 🤍," they captioned the post at the time.

RELATED: Kaitlynn Carter and Boyfriend Kristopher Brock Expecting Second Baby, a Daughter — See Her Bump!

Carter has been candid about enjoying parenthood, calling her first year of being a mom "hands down the best year of my life" as she celebrated Rowan's first birthday in September with a compilation video of moments from his life on Instagram.

At the time, the couple gathered with family and friends to enjoy Rowan's "one in the sun" themed birthday celebration, which saw the little boy enjoy a slide, bouncy house and birthday cake.

Carter, who began dating Brock in May 2020, opened up about their relationship in 2021 during an appearance on the HillsCast podcast, revealing that the couple had started talking about building a family together very early on in their romance.

"When I began dating again, I knew that it was really important to me to find somebody who had the same goals and wanted the same things in life that I did," she said. "So, we got to the conversation about having kids and where we stood with all of that very quickly."