Jenner gave birth to her baby girl Stormi Webster on February 1, and then shared an 11-minute YouTube video that chronicled her pregnancy on February 4.
Thompson, who plays for the Cleveland Cavaliers, had Saturday night off from basketball. After all, Tristan has allegedly been cheating on her for months with multiple women.
Khloe and Tristan's daughter is the third "Kardashian-Jenner" baby girl to be born this year.
The Kardashian family welcomed two more children this year: Kim welcomed her third child, daughter Chicago, via surrogate in January with husband Kanye West.More news: Prince Harry and Meghan Markle won't have political guests at wedding
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TMZ also published a video of Thompson, shot by a surveillance camera in October 2017, at a Washington D.C. hookah lounge.
A report in People magazine on Wednesday quoted an "insider" as saying that the cheating allegations were "a long time coming". Khloe had struggled to conceive in the past and was anxious that she might never be able to be a mother, so today's news is even more special for KoKo and Tristan. "And there will be more women to come out of the woodwork".
Kardashian shared a photo of her growing baby bump with an emotional message to her fans, calling the major life milestone her "greatest dream realized". Though, to be fair, 74.8 million Instagram followers is an insane amount for any person to have - and Kardashian did have a lot of help thanks to her famous family.
After the humiliation Tristan has put her through, Khloe's first reaction is to say goodbye to him once and for all, but at the same time, she doesn't want her child growing up without a dad.
This makes us so happy as Kardashian has always wanted to be a momma. One source said she is in "total disbelief". He made her feel on top of the world and unlike any man she has been with.
This story is developing.