Kris Jenner Says She's 'Blessed' Following the Birth of Khloé Kardashian's Baby Girl

Khloé Kardashian welcomed her first child with NBA boyfriend Tristan Thompson on Thursday, April 12

Kris Jenner is over the moon about her ninth grandchild!

The momager and KarJenner matriarch, 62, confirmed the birth of Khloé Kardashian‘s baby girl on Instagram Thursday. “BLESSED!!” she wrote along with a video of daughter Kendall Jenner repeatedly saying “baby” in a throwback clip from W magazine.

Khloé, 33, welcomed her first child with NBA boyfriend Tristan Thompson on Thursday, April 12, multiple sources confirmed to PEOPLE.

This is the first child for the Keeping Up with the Kardashians reality star while Cleveland Cavaliers player Thompson, 27, is already dad to 16-month-old son Prince Oliver from a previous relationship.

Kris is the grandmother of 9-week-old Stormi, 3-month-old Chicago, Dream Renée, 17 months, Saint, 2, Reign Aston, 3, North, 4½, Penelope Scotland, 5½, and Mason Dash, 8.

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“Khloé labored with [mom Kris Jenner] yesterday at the hospital. Tristan was there for the birth,” a KUWTK source told PEOPLE on Thursday.

Added the source, “He has practice today, but will spend as much time at the hospital as possible.”

Kris flew to Ohio to be with Khloé a day before the birth, according to an insider.

“Kris is in Cleveland giving Khloé as much support as possible,” the insider said. “They’re trying to keep her emotionally stable. The whole family is beyond pissed at Tristan. The goal is to get Khloé out of there as fast as they can without jeopardizing the safety of the baby. Khloé just wants to be home.”

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The baby news comes two days after allegations that Thompson was seen kissing multiple other women and a source calling him “a serial cheater.”

On April 10, videos surfaced of the Cleveland Cavaliers power forward allegedly getting close to an unidentified woman at the PH-D Lounge in New York City over the previous weekend.

WATCH: Born Kardashian: Khloé and Tristan’s Pregnancy Announcement

A man who has been identified as the athlete was seen speaking closely with a brunette in photos and footage published by the Daily Mail and TMZ. The Shade Room later published a video of Thompson and a brunette allegedly entering his hotel at 5 a.m.

TMZ also posted footage recorded in October, allegedly depicting Thompson kissing one woman while a different woman groped him at the Darna hookah lounge outside of Washington, D.C.