Warning: Cuteness overload ahead! While it’s no secret that North West and Penelope Disick spend a lot of time together — ahem, they have a joint birthday party every year — you may not realize just how special their bond is. “North and Penelope call each other sisters, that’s how close they are,” a source exclusively told Life & Style.

“They want to do everything together. It’s hard to take them anywhere separately. They call each other on the phone, they beg for playdates most days and they’ll have sleepovers on the weekend,” the source continued. Of course, a lot of Nori and P’s favorite activities are inspired by their famous moms, Kim and Kourtney Kardashian.

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My girls ❤️

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“They’re always playing dress up and doing each other’s makeup with fake makeup kits that Kim gives them,” the source expressed. “Kris [Jenner] and Kourt and Kim all think it’s so adorable because they really are as close as Kim and Kourt were growing up.” Hmmm, it looks like history really does repeat itself … in more ways than one!

Khloé [Kardashian] was always the one left out growing up and it’s the same with Chicago, but at least she has True and Stormi and Dream.” Considering North, 6, and Penelope, turning 7 in July, are much closer in age, it’s understandable that they leave the little ones out for the time being — especially because the dynamic duo has big plans for the future.

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A True Chicago Stormi ⛈

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“North and Penelope want to start a band together, they’re always singing and performing for their parents,” the source said. “North is a lot girlier than Penelope who likes to be outside more than in the glam chair like North, but they’re a good balance for each other. They go to school together, but they won’t be able to be in the same class — just like twins aren’t allowed in the same class!”

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