North West giving birthday wishes
Credit: Instagram/kimkardashian

Watch out, Kendall and Kylie Jenner: The next generation of Kardashians is stealing the show! North West and her cousin Penelope Disick may be the cutest duo on Instagram, as evidenced by Khloé Kardashian's precious photos and videos. This weekend Khloé pulled double-duty as aunt and babysitter for her nieces (the tots' moms are her big sisters, Kim and Kourtney Kardashian) and documented the experience on Instagram.

One highlight? North, 2, and Penelope, 3, starred in their own Instagram video that's pretty much guaranteed to make you say, "aw!" In it, the girls squeal, giggle, and sing "diamonds" into the camera. Aunt Khloé appropriately captioned the post, "Like a diamond":

The little ones also enjoyed a screening of The Book of Life:

And Khloé also shared a sweet photo of Penelope getting a piggyback ride from her aunt as North looked on: