It's no secret that Saint is yet to impress his older sister.
Kim has often spoken of North's disdain for her three-year-old brother - once telling Ellen DeGeneres that her daughter "hardly talks" to Saint.
Baby Psalm is rarely seen in the reality star's photos.
The infant was last seen on her Instagram on July 20 as he snuggled with his big brother Saint.
While Kim's third child, Chicago West, didn't appear in the photo, she was recently seen on Khloe Kardashian's Instagram with cousin True Thompson - Khloe's daughter - in the Bahamas.
The new post featured the one-year-olds snacking on Cheetos and veggie straws, accompanied with a funny caption from Khloe:
"Chi: I heard my mama say 'vacation calories don’t count.' True: 'Don’t tell me twice Chi.'"
The little ladies could also be seen rocking their cutest one-piece swimsuits.
Another photo featured the two girls enjoying some cold water while True rocked a pair of white sunglasses.
Kylie Jenner commented on the post: "Beautiful babies. Miss them."
Kim also commented, "Our babies," adding two love heart emojis.
The KKW Beauty founder recently shared several photos of the Kardashian family trip to the Bahamas, including a photo of her wearing a bikini while on the beach with several pigs in the Bahamas.