“My sweet Stormi and Psalm,” Kardashian West, 39, captioned the sweet shot of the cousins.
The Keeping Up with the Kardashians reality star often shares photos on social media of her four children with husband Kanye West: sons Psalm and Saint, 4, and daughters North, 6, and Chicago, who turns 2 on Wednesday.
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On Saturday, Kardashian West reminisced about Psalm and Saint’s brotherly bond with a “flashback” photo of the siblings when they were younger.
In December, the mom of four posted a throwback photo of her youngest and eldest children together on Instagram. “Flashback to when Psalm was so little. My baby Northie is so helpful,” the mom of four wrote along with an adorable photo of North and her baby brother.
“How are my babies getting so big,” Kardashian West added, with a cry face emoji.
Jenner, meanwhile, recently went down memory lane by posting a throwback Instagram photo of herself pregnant with daughter Stormi, whom she shares with ex Travis Scott.
“Throwback🤰🏻pregnant with my baby girl,” the 22-year-old makeup mogul captioned the sweet shot, along with a hashtag of her daughter’s name. “I can’t believe my daughter will be two soon..🖤”
In the picture, Jenner can be seen showing off her bare belly in a black crop top and maroon sweatpants.
Jenner welcomed her first child on Feb. 1, 2018. The Kylie Cosmetics founder famously kept her pregnancy a secret from fans, only confirming it on social media days following the birth of her first child.
“I’m sorry for keeping you in the dark through all the assumptions,” she wrote in an Instagram post at the time. “I understand you’re used to me bringing you along on all my journeys. My pregnancy was one I chose not to do in front of the world.”
Jenner added, “I knew for myself I needed to prepare for this role of a lifetime in the most positive, stress free, and healthy way I knew how. There was no gotcha moment, no big paid reveal I had planned. I knew my baby would feel every stress and every emotion so I chose to do it this way for my little life and our happiness.”
“Pregnancy has been the most beautiful, empowering, and life changing experience I’ve had in my entire life and I’m actually going to miss it,” she said. “I appreciate my friends and especially my family for helping me make this special moment as private as we could.”
PEOPLE confirmed in October that Jenner and Scott, 27, had decided to take a break from their relationship after over two years together. Jenner publicly confirmed the news a few days later, tweeting, “Travis and I are on great terms. Our main focus right now is Stormi. Our friendship and our daughter is priority.”