So True? So False? Did Scott Disick Hook Up With Kristin Cavallari?!

E! star was rumored to be banned (by Kourtney) from Dancing With the Stars until the Hills star, whom he supposedly hooked up with while temporarily single, was gone

Did Scott Disick get lost in The Hills a couple years ago?

We didn't think too much of Kourtney Kardashian's longtime boyfriend and partner in parenting not showing up at Dancing WIth the Stars to cheer for Rob Kardashian until Halloween night.

But, according to a très scandalous Life & Style story, Disick wasn't there because he was unofficially banned from the ballroom until Kristin Cavallari had been voted off—because the two of them hooked up while he and Kourtney were on a break in 2009, before she got pregnant with Mason!

These reality-TV stars do make the rounds, and Scott does like a woman whose name starts with K. Hang onto your cravats, kids, because this story is...

So false!

A source close to Cavallari, actually, told E! News that the alleged hookup never happened and that she finds the very idea of it "gross."

In other Cavallari news, the source added, the former Hills star is back with ex-fiancé Jay Cutler—who did make the pilgrimage to Dancing With the Stars during the three weeks she was on the show.

But we can't forget Cavallari's hot date for tomorrow night! The leggy blonde will be on the arm of U.S. Marine Jonathan Burkett, who invited her via Twitter, at the Marine Corps Ball in San Diego.

"So excited to have a fitting with @judy_thekids @sammyrexic for my dress for the marine ball tomorrow night," Cavallari tweeted today.

"@KristinCav well glad your looking forward to it! Will be a blast for sure," Burkett wrote her.

UPDATE: "Glad u guys know what's up and don't believe bs! Love u guys," Cavallari tweeted on Nov. 17.