kim kardashian
Credit: kimkardashian / instagram

Happy Birthday, Penelope Disick! The adorable daughter of Kourtney Kardashian and Scott Disick, lovingly nicknamed "P," turned four yesterday, and her family has been taking to social media to show their love. Kris Jenner, Khloé Kardashian, and proud mom Kourtney have each shared birthday wishes on Instagram, and last night aunt Kim Kardashian West did the same, sending a sweet message to her niece with an impossibly cute candid capture.

In the Instagram video, Kardashian West catches the birthday girl at play with her daughter, North West. The adorable duo sings loudly in unison while holding hands and dancing on chairs. "Whatever secret language u girls speak, the way you girls protect each other & love each other is so special," Kim writes. "Penelope, North is so lucky to have a best friend like you! Happy Birthday my sweet P. I love you to the moon and back!" The playmates are so enamored with each other's company that they haven't even touched their meals, seen unfinished on the place mats behind them.

Though the pre-schooler and reality TV starlet already enjoyed an extravagant mermaid-themed joint birthday party with North last month, there are sure to more birthday surprises in store for little P over the weekend.

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