The Keeping Up With The Kardashians star, 35, announced the birth of her second child on 5 December - but hasn't shown us any pictures of him on social media until now.
On Sunday (3 January), in a post to her 56.4million Instagram followers and 38.6million Twitter fans, Kim shared an adorable photo of her four week old son Saint clasping big sister North's finger. Too cute!
Alongside the snap, Kim wrote: "She said, 'He's my best friend'."
One fan simply responded with the message "priceless", while another gushed: "Cuteness overload."
The week before, Kim had shared a picture with her mini-me daughter North, who will turn three in June.
Taken from behind, the snap shows both mother and daughter wearing matching braids at Kris Jenner's famous Christmas Eve party.
North welcomed her little brother four weeks ago.
A statement on Kim's official website said: "Kanye and I welcome our baby boy!"
It's believed she and husband Kanye West named their son Saint as he's a "blessing".
She has since insisted she won't be having any more kids!
For exclusive competitions and amazing prizes visit Reveal's Facebook page NOW!