Kim Kardashian’s daughter, 2-year-old North West, has a little brother now Credit: Kim Kardashina/Instagram

North West just got a new playmate! Kim Kardashian and Kanye West’s 2-year-old daughter officially welcomed a new baby brother on Saturday, Dec. 5, and Us Weekly has good reason to believe that Kimye’s tiny tot will make a great big sister.

North, better known in the Kardashian-Jenner clan as Nori, has a best friend in cousin Penelope Disick, 3, and the pair have been photographed having fun doing everything from dressing up as mermaids to enjoying post-bath downtime together.

And in August, when the entire reality family headed to St. Barts for a summer vacation, North happily played with Penelope and frolicked in the water with her other cousin, 5-year-old Mason.

Night Night 👼🏽👼🏼

A photo posted by Kim Kardashian West (@kimkardashian) on

Kimye revealed on Monday, Dec. 7, that they've named their son Saint West.

While it will be quite a few months before Nori’s little brother will be able to romp around with his sis, she’s already had plenty of practice playing with baby boys in the form of Kourtney Kardashian’s youngest child, Reign, 11 months.

These love bugs! #HappyBirthdayP

A photo posted by Kim Kardashian West (@kimkardashian) on

“Nori is very active,” a source told Us about the little girl back in August. “North can’t wait to be a big sister and feels Kim’s belly.”

In October, Kardashian, 35, admitted that she was a bit “nervous” about introducing North to her new little brother.

Bubbles & Minnie Mouse kinda day!

A photo posted by Kim Kardashian West (@kimkardashian) on

“Not going to lie, I’m a little nervous about bringing baby No. 2 into the mix,” the Selfish author wrote on her blog on Friday, Oct. 23. “I’m nervous about how North will react, but I know she’ll be such a good big sister and I can’t wait to have this addition to our family. I know it won’t be easy — North even has a hard time adjusting when I hold other babies!”

To ease North into the idea of sharing mommy and daddy, Kardashian and West, 38, have been reading “books with her about getting a baby brother” and “always say goodnight to baby brother.”

“Right now anything her cousin Penelope does, she does,” Kardashian wrote. “So it’s helpful that P has a little baby brother!!!”

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