Rumors are swirling Kendall Jenner might be pregnant by older sister Kourtney's longtime partner Scott Disick.

Star Magazine reports that reality would be Kourtney Kardashian's worse nightmare and just the thought of it is already starting to take its toll on her.

"She can't sleep at a night," a source told the website. "And when she does, she wakes up in a cold sweat, crying, after dreaming that Kendell is pregnant with Scott's baby."

For weeks now, rumors have circulated that 19-year-old Kendall was hooking up with the much older Disick. But according to HollywoodLife.com, it could all be part of Disick's plan to perpetually agitate the mother of his three young children.

"Scott loves getting under Kourtney's skin all the time," a source told HollywoodLife.com

The 35-year-old Kardashian and Disick's relationship has long been a volatile one. Last summer while Kardashian was still pregnant, the couple regularly quarreled after Us Weekly reported Disick "reverted to his hard-partying days" while the couple was spending time in the Hamptons vacationing over the summer.

"Kourtney was yelling at Scott after she found an inappropriate picture of him with another girl," a source told the magazine.

At the time, Disick was mourning the death of both of his parents.

Still, during an episode of the reality show "Kourtney & Khloe Take the Hamptons," Kourtney Kardashian took him to task, admonishing, "you need to be a more responsible father and get better. There is another baby on the way. You need to straighten up or get out."

In days past, Khloe Kardashian has blasted the rumors as absurd. "I'm really pissed about this whole @KendallJenner and @ScottDisick thing," she posted to social media. "Scott, I thought it was you and I that was having the affair."

She continued: