“Keeping Up With the Kardashians” star Kourtney Kardashian and businessman Scott Disick split in July after he spent Independence Day away from his family in Monte Carlo, but rumors have swirled that Kardashian was the one fooling around behind the self-proclaimed Lord’s back. In fact, Disick might not even be the father of their youngest child, Reign, OK! magazine wrote in an exclusive report, according to Hollywood Life.

“There’s been buzz in their circle that Kourtney cheated and Reign might not be Scott’s,” an insider said. “Everyone’s been saying, ‘Poor Kourtney,’ and she’s been made to look like the innocent party. It’s pretty harsh of her to make him take all the blame for a situation she may have had a hand in.”

The businessman was accused of cheating on Kardashian, 36, with his ex-girlfriend, Chloé Bartoli, after paparazzi captured them sitting close to each other, with Disick’s hand on her back. The Lord, who also stars on “KUWTK,” never admitted to the alleged affair.

But when Disick, 32, heard Reign might not be his child, he was shocked. “He flipped when he heard it, and he’s been off the rails ever since,” the source said. “He’s behaving strangely. There’s definitely something going on.”

Though Disick likes to share pictures of his eldest children, Mason Dash, 5, and Penelope Scotland, 3, on social media, he rarely, if ever, shares pictures of his baby boy, Hollywood Life noted. For Penelope’s birthday, he wrote a touching yet sad message to his only daughter. He shared a collage of photos of the toddler and then captioned the image, “1 of the only things I'm proud off about myself. Happybdayp.” The post received more than 790,000 likes from his 10.6 million followers.

His most recent post is about P (as her family affectionately calls her) and Mason listening to Demi Lovato’s hit song “Cool For The Summer” in one of his cars. The summer jam is blasting and the kids adorably dance in the front of the car.

There’s a chance Disick might give Reign a shout-out on his Dec. 14 birthday. He coincidentally shares a birthday with his oldest brother. Maybe a double shout-out?

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