Duff Sisters Join Hersey Ice Breakers Campaign

Hilary Duff and her sister Haylie are the latest duo in the Hersey's Ice Breakers Liquid Ice campaign. The pair, who claim never to disagree in real life and who replace Jessica and Ashlee Simpson in the campaign, can't seem to agree on the product's liquid versus ice qualities. The campaign includes a website where visitors can answer stupid questions like, "What weighs more - a pound of ice or a pound of water?" and other noggin stretching gems.

"We agree on absolutely everything, especially the importance of fresh breath," said Hilary. "So when she thought that Ice Breakers Liquid Ice was liquid and I thought it was ice, well I knew she had to be right ... and she knew I had to be right!" Haylie said, "One thing we're both right about: Ice Breakers Liquid Ice totally rocks!" Like, OMG!!!!!!!