Kristin Cavallari: I Didn't Have An Affair With Scott Disick!

Kristin Cavallari has hit back at reports that she had a fling with Kourtney Kardashian's boyfriend Scott Disick. The former Dancing With The Stars contestant is also furious with the famous reality clan for not yet denying the claims.

The 24-year-old even went so far as to suggest that the family are staying quiet in order 'to keep the heat off Kim,' who is currently going through a divorce with husband Kris Humphries.

Kristin Cavallari isn't the cheating type -- despite what one tabloid mag wants its readers to believe.

'It's 100 percent not true,' she said on The Billy Bush Show yesterday. 'I just think, what convenient timing for them (Kardashians) with their show premiering next week.

Kourtney Kardashian put on a brave face yesterday
as reports emerged that her partner Scott
had an affair whilst the couple were on a break

'With everything that's going on for Kim, I feel like they're trying to take the heat off her.When there's a big story like that, they always call you and ask if you want to comment and clearly none of them denied it.'

She added that her on/off fiance and NFL player Jay Cutler was backing her. '(He) didn't believe (the report) for one second,' she said. The livid star said that the Kardashian's reluctance to speak out about the rumours was just plain rude. 'It's disrespectful to me and Jay,' she said. 'I think it just says a lot about their character.'

Today Kourtney's representation told the Mail Online that the story is not true. Yesterday Kourtney put on a brave face as the reports emerged that partner Scott had a fling with Kristin while the couple were on a break. The 32-year-old smiled as she posed with younger sister Khloe at a signing for their new book Dollhouse in New York City.

Kourtney's current boyfriend and father of her one-year-old son Mason was accused of 'hooking up' with Kristin in 2009 in a report published by American magazine Life&Style.

The fling is said to have occurred just before Kourtney fell pregnant. According to the insider, they first met up during a trip to Las Vegas. 'Scott and Kristin hooked up in Las Vegas during a time [February 2009] that he was on a break from Kourtney,' the source said.

Kourtney's representation told the Mail Online that the story 'is not true'.

Kristin did her date proud last night, after braving hellish LA traffic to escape the city and head north for  the date. The 24 year old shrugged off the drama to attend the Marine Corps Ball in Temecula, California.