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Hills Spoiler Alert: Lauren, Holly and Heidi, Oh My!

Wed., Nov. 12, 2008 12:20 PM PST by Marc Malkin

Holly Montag, Lauren Conrad, Heidi Montag

Amanda Edwards/Getty Images for American Eagle; Chris Weeks/Getty

Warning: If ya don't want to know what happens next on The Hills, stop reading right now!

Did Heidi Montag actually kick her own sister, Holly, to the curb?

In next week's episode of MTV's hit pseudo-reality show, Holly moves in with—drumroll, please—Lauren Conrad.

Referring to L.C. as her "new roomie," Holly revealed at last night's launch party for the new Shaun White Snowboarding video game that she's living with her sister's one-time nemesis "for a little bit."

Of course, the move did not come without some drama. Holly was tight-lipped when asked for the juicy details, so we did some diggin'.

A source says highlights of the episode include Montag complaining to Conrad that her own sibling gave her the boot from her and Spencer Pratt's apartment.

"Heidi practically booted me out herself," Holly tells Lauren in the episode. "I thought it was just Spencer."

Cut to Heidi telling Pratt, "Am I going to never talk to my sister again? Are we not going to be friends?"

Still no word on how long the Holly and Lauren slumber party is expected to last.