Kim Kardashian is "so happy for" her sister Khoe following the news that she gave birth this week.

On Twitter Thursday (April 13), Kim gushed about her younger sister's new bundle of joy, calling Khloe "strong."

"Khloe Kardashian, I’m so happy for you! Your baby girl is so beautiful! You are so strong, you made that look so easy," she tweeted.

Kim, a mother of three, also revealed that she was alongside Khloe in the delivery room, writing, "I’m so happy I was able to return the favor of holding your leg while you pushed."

In another tweet, the reality TV star, who welcomed baby girl Chicago back in January, bragged that Khloe's new baby is "so gorgeous," and that she " can’t wait for our baby girls to grow up as best friends the way we are."

While Kourtney, Kendall and Rob have yet to congratulate their sister publicly, Kylie was the first sibling to celebrate Khloe's daughter's birth, posting on Snapchat, "Kongrats, Khloe! It’s a girl!"

"#BLESSED" mom and new grandmother Kris Jenner also congratulated Khloe on social media, re-posting a hilarious video of Kendall saying "Baby, baby, baby!" to Instagram.

Khloe gave birth to a baby girl on Thursday, April 12, in a hospital located just outside Cleveland, Ohio. Kim, Kourtney and Kris were reportedly present when she gave birth to her and boyfriend Tristan Thompson's first child.

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