Scott Disick Cheated on Kourtney Kardashian With Kristin Cavallari

“Scott Disick, why you no sit with Kardashian to support Rob while he Dancing With Stars?,” asked Kardashian fans in their pigeon English. Well, he did, but not until October 31. Before then, he was banned from the tapings by Kourtney. Mainly because she was a little pissed that he cheated on her with Kristin Cavallari, also a DWTS contestant, before she was pregnant.

“While Kourtney and Scott were on a break, Scott hooked up with Kristin,” a friend reveals to Life & Style.

So when both Rob and Kristin were confirmed as contestants on DWTS, “Scott and Kourtney argued about Kristin,” a friend confirms. “Kourtney can’t stand her now and didn’t want Scott at show tapings.”

A Kardashian pal confirms that “Scott and Kristin hooked up in Las Vegas during a time [February 2009] that he was on a break from Kourtney.” The Kardashian pal adds that Kristin, Kourtney and Scott were best friends with Kristin during her Laguna Beach days and even after Kristin stopped dating Kourtney’s stepbrother Brody Jenner. Hanging out at Brother Jimmy’s in NYC or dancing at the Fontainebleau Hotel in Miami, the three reality stars were close until Kourtney first caught Scott and Kristin on a date at Apple Lounge in LA on March 11, 2009. Life & Style

It wasn’t a one time thing either. “Scott and Kristin were hooking up on and off for a year, maybe even two. When Kourt and Scott would fight, he’d party with Kristin and hook up,” says another source. Kourtney has been mad at Kristin ever since and she and her sisters have taken to calling Kristin “the whore bag.”

Uh, I believe the term is “ho bag,” but I digress. This is not surprising. Scott Disick seems like a gigantic douche. Now, it would be surprsiing if he wasn’t banging another reality show has-been on the side.

“Up top is Kristin Cavallari heiling Hitler” — Kourtney Kardsahian. Oh, real mature, Kourtney.