The birth of Khloé Kardashian‘s first child should have been the happiest day of her life.
But the milestone is now tainted by boyfriend Tristan Thompson‘s cheating scandal, which broke just as the nine-months-pregnant reality star is about to give birth to their baby girl.
On Tuesday, photos and videos surfaced of Thompson allegedly getting close to an unidentified woman at an N.Y.C. lounge over the weekend. TMZ also posted footage recorded in October 2017 allegedly depicting Thompson kissing one woman while a different woman groped him at the Darna hookah lounge outside of Washington D.C.
“Tristan has been consistently cheating on Khloé,” a source alleged to PEOPLE. “He’s a serial cheater. And there will be more women to come out of the woodwork.”
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Kardashian and Thompson’s reps did not immediately respond to PEOPLE’s request for comment.
Meanwhile, Kardashian’s famous family members “are heartbroken for Khloé,” a source said. “They didn’t realize how deceptive Tristan could really be.”
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“He was her everything. They had a life together. She honestly thought he treated her like gold, like a queen,” the source said. “[He] gave her everything, doted on her, told her how beautiful she was. To her, life was perfect. And it all just came crashing down.”
Kardashian, 33, and Thompson, 27, have been dating since late summer 2016; multiple sources confirmed to PEOPLE in September 2017 that they are expecting. Kardashian publicly confirmed her pregnancy news in December.