It wasn't your ordinary Hollywood premiere for "Cheaper by the Dozen" on Sunday -- at least, not after teen stars Hilary Duff and Lindsay Lohan were through.

The New York Post reports that Lohan, 17, and Duff, 16, have been at odds most of this year, ever since Lohan and Duff both once dated teen-pop pinup Aaron Carter. Things got even chillier over the summer, when Duff showed up at the premiere of Lohan's "Freaky Friday" on the arm of Lohan's onscreen boyfriend, Chad Michael Murray.

As for the "Cheaper" chaffing, the Post says Duff's mother, Susan, attempted to get the teen star's bodyguard to oust the diminutive Lohan out of a post-screening party at Lucky Strike Lanes in Hollywood.

The Post reports that Lohan's agent told her to stay put, which only prompted the bodyguard and Susan Duff to step up their campaign to show the young star the door. This caused Lohan to say: "I am not leaving. I was invited. Why should I leave?"

Mother and daughter Duff then took their case to studio executives -- except they, too, told Lohan to stay, the paper reports.

So the Duffs reportedly departed, leaving Lohan to party with Demi Moore, Ashton Kutcher and "Cheaper" star Steve Martin.

Lohan's rep confirmed the Post's reportage, but Duff's rep said: "I did see Lindsay at the party, but their paths never crossed. Hilary was on the couch the whole time talking to Demi. She had to leave early because she had an early flight to Boston the next day for a concert."