Kim Kardashian Describes Bond Between North, Penelope, Mason

Khloe Kardashian, Kim Kardashian and Kourtney Kardashian, left to right, arrive at the Tao Nightclub at The Venetian Las Vegas to celebrate Kim Kardashian's 33rd birthday on Oct. 26, 2013 in Las Vegas. (Credit:Ethan Miller/Getty Images)

Before Kim Kardashian gave birth to North West, there were two other tiny Kardashians in the mix: Kourtney's two children, Mason, 3, and Penelope, 1.

Now, according to Kardashian, all the kids have formed a mini-clique.

"Its so cute how they all love each other so much!" Kardashian, 33, tweeted.

"Penelope & North are bff!" she continued. "Mason bosses them around and is super protective."

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It's a good thing that everyone gets along, as the "Keeping Up with the Kardashians" star added that they'd be spending Christmas together.

"The entire family, Kanye, North, mom, sisters, step dad, brother, neicem[sic] nephew, everyone!" she wrote. "They are all my family, and we will all be together! I can't wait"