The baby girl was born Monday, Jan. 15, at 12:47 a.m., weighing 7 lbs., 6 oz.
“Kanye and I are happy to announce the arrival of our healthy, beautiful baby girl,” Kardashian West wrote in a post titled “She’s Here!”
“We are incredibly grateful to our surrogate who made our dreams come true with the greatest gift one could give and to our wonderful doctors and nurses for their special care.”
“North and Saint are especially thrilled to welcome their baby sister,” adds the new mom of three.
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The Wests tied the knot in Florence, Italy, in May 2014, seven months after their engagement and almost a year after the arrival of daughter North. Kardashian West, 37, gave birth to son Saint in December 2015.
“The entire family is over the moon. Kim had been looking for a surrogate for months until recently when she found the perfect candidate,” a source told PEOPLE in September, explaining the logic behind the family choosing surrogacy had to do with Kardashian West’s battle with placenta accreta in both her previous pregnancies.
“Given her health scares in the past, Kim felt the need to hire a surrogacy agency that helped serve as the liaison in finding a healthy woman who would be a great surrogate option for her and Kanye,” the source added. “Both of them have been super involved in the process.”
Two days after news of the pregnancy broke, a source told PEOPLE the baby on the way would be another girl for the family — and that the spouses were “thrilled,” sharing, “They are so excited about their future baby girl.”
Of the cherry-blossom-themed soirée she’d been the guest of honor at recently, the KKW Beauty mogul told Ellen DeGeneres, “My daughter thinks she’s tricky. We had a baby shower over the weekend, and I thought, ‘You know, I really do want to have a baby shower because I want [North] to feel that something’s coming and for her to really understand it.’ ”
She continued, “So, people brought toys and gifts and [North] was opening them all up the next day. And she goes, ‘Mom, since Baby Sister’s not here, I think I need all of her toys in my room and [to] play with them and make sure they’re all okay for Baby Sister.’ “
An insider divulged to PEOPLE in December that Kardashian West “isn’t sharing the name” before her baby’s birth, citing her secrecy ahead of North and Saint’s births and adding, “Kim and Kanye are letting North help with naming the baby.”
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“Anyone that says or thinks it is just the easy way out is just completely wrong,” said Kardashian West. “I think it is so much harder to go through it this way, because you are not really in control.”
“Obviously you pick someone that you completely trust and that you have a good bond and relationship with, but it is still … knowing that I was able to carry my first two babies and not my baby now, it’s hard for me,” she explained. “It’s definitely a harder experience than I anticipated just in the control area.”
The new little girl is the first to arrive during a bit of a KarJenner baby boom. Kardashian West’s sisters Khloé Kardashian and Kylie Jenner are both expecting their first children in early 2018 — a girl for Jenner, 20, and a boy for Kardashian, 33.
But despite the closeness in their kids’ ages, there is no jealousy among the trio. As a source divulged to PEOPLE in October, “If there will be any friction at all, it’s that everyone is in each other’s business. But that’s like any close family.”
“There is no jealousy here,” added the close family insider. “No one is worried about anyone stealing their thunder. It’s not dramatic like that.”