Kim Kardashian West couldn't be happier that her younger sister Khloé Kardashian has welcomed her first child, a baby girl

By Maria Pasquini
April 13, 2018 11:16 AM

Kim Kardashian West couldn’t be happier that her sister Khloé Kardashian has welcomed her first child!

“@khloekardashian I’m so happy for you! Your baby girl is so beautiful! You are so strong, you made that look so easy!” the Keeping Up With the Kardashians star, 37, raved in a Friday tweet, one day after Kardashian gave birth to her and boyfriend Tristan Thompson‘s daughter.

The mother of three went on to share the heartwarming message that she “can’t wait for our baby girls to grow up as best friends the way we are.”

Kardashian West welcomed now-3-month-old daughter Chicago on Jan. 15. She and husband Kanye West are also parents to son Saint, 2, and daughter North, 4½.

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The KKW Beauty mogul also let fans in on how she helped her younger sister out in the delivery room, writing, “I’m so happy I was able to return the favor of holding your leg while you pushed LOL.”

Unable to stop herself from raving about the Revenge Body host’s daughter, Kardashian West added in a separate tweet, “You guys she’s so gorgeous!!!!!”

Dia Dipasupil/Getty Images

Kardashian gave birth on Thursday, just two days after news broke that her 27-year-old boyfriend had been allegedly photographed and videotaped with a number of different women throughout her pregnancy.

The 33-year-old’s momager Kris Jenner was the first member of the famous family to publicly congratulate Kardashian on the arrival of her little one, sharing a throwback video clip of daughter Kendall Jenner repeatedly saying the word “baby.”

Kylie Jenner, who’s also a new mom to 10-week-old daughter Stormi, went on to celebrate the happy news by sharing a photo of a long, winding road with a pink filter and the words, “Kongrats, Khloé! It’s a Girl!”

Kylie Jenner, Snapchat, April 12, 2018
Jerritt Clark/Getty Images

RELATED VIDEO: Tristan Thompson Booed During First Game Since Allegations He Cheated on Pregnant Khloé Kardashian

Despite the infidelity allegations surrounding Thompson, a Kardashian family source recently told PEOPLE that the Good American designer had “basically already forgiven” the NBA player.

“Khloé is feeling nothing but happiness right now. She is head over heels in love with her little girl — she is just consumed with love. Absolutely nothing else matters,” the insider said.

“She’s so incredibly happy that her baby is here, that she is big and strong and healthy and beautiful, and so right now Khloé truly has no other cares in the world. She isn’t even mad at Tristan right now,” the source continued.