Reality Rewind! Inside Lauren Conrad's 'Rage' Over Kristin Cavallari's TV Comeback

Kristin Cavallari is all over the place as she promotes her new TV comeback Very Cavallari — and former Hills rival Lauren Conrad is jealous as hell!

An insider tells RadarOnline.com exclusively: “LC’s never understood the appeal as far as Kristin goes, so it burns her to see all this headline-hogging and ‘look at me’ behavior from someone she considers a lot of hot air."

Conrad, 32, clearly hasn't moved past the feud that ended over a decade ago. "She thinks it’s pretty classless of Kristin not to be more grateful about what’s gotten her any exposure in the first place — which is The Hills," said the source, adding, "Lauren can’t figure out why she comes across as Little Miss Perfect."

Pals of the pair tell RadarOnline.com exclusively Cavallari, 31, thinks Lauren’s just "a jealous has-been" and "rolls her eyes to this day when her name comes up."

"The bad blood between these two is as bad as it’s ever been.”

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