Kristin Cavallari Was Surprised by Heidi’s Post-Surgery Body

 Denise Truscello/WireImage

Kristin Cavallari was surprised that Heidi Montag decided to drastically alter her body by going under the knife 10 times in just one day in November. (Montag showed off her bikini bod in public for the first time two weeks ago.)

But Cavallari doesn't criticize her Hills co-star, 23.

"It's not my body," she told at the Liquid Pool Lounge at Aria Resort & Casino in Las Vegas Saturday. "If she's happy, that's all that matters."

VIDEO: Heidi struggles to eat a burger after surgeries

One thing she's not surprised about: Montag and Spencer Pratt's diva behavior. Montag recently showed up to a Hills photoshoot with six bodyguards and refused to participate in a cast shot.

"Nothing shocks me about them anymore," said Cavallari, 23, who bared her own bikini bod Saturday, covering up slightly with a midriff-baring, sheer black top. "It's one thing after another."

PHOTOS: The Hills stars – the way they used to look

What's next for her now that The Hills is wrapping up after the sixth season (premiering April 27)?

"I'd like to do some producing," Cavallari told Us. "I have a couple of ideas for reality shows in the works. I really enjoy being behind the camera."

She won't be appearing in front of the camera on the Hills after this season, despite telling E! Online Friday night there's a "possibility" MTV could extend the show by 12 episodes.

PHOTOS: Have these stars had surgery?

Said Toni DiSanto, MTV's president of programming and development, to Gossip Cop, "This is truly the last of The Hills because we want the season to go out on a high note that the show deserves and that the fans deserve.

"This season delivers the drama, the story and the organic culmination of the story," he added.

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