The photo shows North and Penelope wearing identical pigtail buns. The pair are all smiles as they hug each other and another friend.
North and Penelope celebrated their respective birthdays at a joint Moana-themed party in June. Kim and Kourtney gifted the cousins with matching Pomeranian puppies earlier in the month, which they named Sushi and Honey.
"Sister puppies for North & P! Penelope named hers honey," Kim wrote June 17. She later announced North's "puppy's name is Sushi."
Kim is also parent to 20-month-old son Saint with West, while Kourtney shares Penelope, 7-year-old son Mason and 2-year-old son Reign with ex-partner Scott Disick.
Kourtney told Harper's Bazaar in 2015 that North and Penelope both "love" shoes.
"Last night North was over and they were fighting over shoes in Penelope's closet and they were so cute," she said. "By the end they were sharing and trying the shoes on each other and having so much fun. It reminds me of how Kim and I were when we were little girls."
Kim confirmed in an interview with The Hollywood Reporter published Wednesday that she and West are "trying" for a third child.
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