Cavallari recently welcomed her first child Camden but Conrad told Us Weekly that they are not close.
"I don't talk to Kristin anymore," she said.
Meanwhile, Hills star Audrina Patridge told Celebuzz earlier this month that she is not in touch with Conrad.
"I don't really talk to Lauren or see her at all," she said. "I think there was a little of a falling out. We kind of went our separate ways. The show brought us together and without that show, we all kind of go back to our own thing."
Patridge, who revealed that she speaks with Cavallari, Stephanie Pratt, Brody Jenner and Justin Bobby, also ruled out a Hills reunion in the near future.
"Give it another year or two years, because then everyone will be established," she said. "I feel like between two years ago and now, everyone is transitioning and figuring it out."