Kim shared a photo of her as a child alongside one of Saint, writing that he's her "twin in every way."
"This is a screenshot of Keeping Up With The Kardashians," Kim wrote on Instagram. "Look at what a little chunk Saint was! OMG My baby!!!!!! I miss him this small!!!!"
Two weeks after Saint's dinosaur-themed fourth birthday party, Kim shared a few snapshots from the event to Instagram. "Kanye and I threw Saint the coolest dinosaur party for his 4th birthday!!! He had so much fun! Thank you @mindyweiss," she captioned the December 2019 post.
"I have no words to describe how much I love your smile and those curls of yours Saint! You bring so much joy into my soul. You are so kind, loving and just so thoughtful and sweet! I am so happy today if your 4th birthday and We get to celebrate how much you've grown!" Kim shared in honor of her eldest son's big day.
Saint poses with a friend in this smiley shot. "Happy Sunday! These cuties always make me smile," Kim posted.
Saint got some shut-eye!
Kim and Saint made funny faces in an adorable Instagram post from August 2019.
Kanye lets his son throw out the ceremonial first pitch before a Chicago Cubs-White Sox game.
"Guess who," Kim asked on Instagram.
"These two are inseparable #Chi #Saint," Kim wrote with this perfect pic.
"My Favorite boy," Kim tweeted with this snapshot of Saint swimming.
Kim lovingly called son Saint her "boo" in this tender moment shared on Instagram.
Saint couldn't take his eyes off gorgeous mom Kim in this family snap!
Kim proved "we all need hugs" with this sweet Instagram pic of Saint and Chicago!
Saint flashed a smile while out with mama Kim.
Saint cozies up to dad Kanye while enjoying the 2017 Kardashian Christmas Eve party.
Kim posted a pic of Saint on her app for his birthday, while also previewing the Kardashian Christmas card. "DAY 5- HAPPY BIRTHDAY to my beautiful boy Saint! I love you so much! You don't even understand!!!" Kim captioned the pic.
Saint hops in his car seat for a drive.
Kim Snapchatted Saint looking beyond adorable in an animal filter.
North and Saint cuddle up to mommy during a star-studded Fourth of July party.
Kim posted this cute photo of Saint crawling on Instagram.
Saint looks adorable in this pic with mom Kim.
Kim and Saint took this sweet selfie together.
Kim captioned these pics, "Me and my Sainty boo a few months ago."