While wishing little Reign a happy first birthday on Monday (14th December), the reality star shared her hopes that Saint and Reign would grow up to be as close as she is to her own siblings.
(Reign shares his birthday with big brother Mason, six.)
Kim said: "Happy Birthday to the sweetest baby Reign. Explaining to Mason that his little brother wanted to be just like him that he even took his birthday was a fun task lo. I can't wait for you & Saint to be bffs."
No doubt newborn Saint, who arrived on 5 December and is the son of Kanye West, will become super close to Reign considering how important family is to the Kardashian Jenner clan.
Kim's daughter North, two, is best friends with Penelope Dash Disick, the three-year-old sister of Reign and Mason. Their mum is Kim's big sister Kourtney.
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