Kim and Kanye with their three oldest children, Saint, North and Chicago.
She tweeted this small piece of information about their new addition, writing: "He's also Chicago's twin lol I'm sure he will change a lot but now he looks just like her".
Kardashian West previously told guests - including momager Kris Jenner and sister Kourtney Kardashian as well as Chrissy Teigen, Paris Hilton, Larsa Pippen, Jen Atkin and E! stars Olivia Pierson and Natalie Halcro - at the baby shower that she felt like she was in over her head.
The extended Kardashian-Jenner family.
The birth comes after she disclosed she's studying to be a lawyer through California rules that allow for professional mentorship over law school.
Kardashian hasn't shared a photo of their baby boy yet, but she did post photos from her baby shower and revealed a bit more information about their newest family member. News at the 2019 Race to Erase MS Gala in Beverly Hills honouring Selma Blair, shortly after her 10th grandchild's birth, Kris said: "I have a cough".More news: Premier League Golden Boot: Mohamed Salah, Sadio Mane & Pierre-Emerick
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She wrote: "He's here and he's flawless! So, they wouldn't let me come to the hospital so, I'm a little annoyed".
"I thought it was kind of ridiculous to have a fourth baby shower".
Of course, the Kardashian family Mother's Day tributes didn't stop there!
Kanye West paid tribute to his late mother Donda West during his first live-steamed Sunday church service on Mother's Day. Thank you for the being the best inspiration for all of your kids and showing us to work hard and love harder!
Kris also included a special thanks for her own mom, Mary Jo "MJ" Campbell, sharing, "To my incredible Mom MJ, I love you more than you will ever know".