LOS ANGELES -- Hilary and Haylie Duff had a blast covering "Our Lips Are Sealed," but remaking "Material Girl" is more up their alley.

"We grew up rocking out to Madonna when we were younger," Hilary said. "We would make up dances when we were little kids to her music. We feel honored to get to do this."

The sisters will record the Madonna classic for the soundtrack to "Material Girls," a comedy about sibling heiresses who lose their father's fortune in the wake of a scandal and are forced to fend for themselves (see [article id="1493477"]"Duff Sisters To Channel The Hiltons, And Possibly Madonna, For 'Material Girls' "[/article]).

"We are so excited," Haylie said. "It's just a crazy script and crazy characters and really high energy and it's really funny. Their personalities are crazy and the outfits are going to be cool and hopefully it will have an interesting cast. There's a lot of little parts in there and hopefully we can get our friends to be in it as well."

The sisters in the movie are heiresses (named Persia and Tanzie, no less), but it's "not the story of [the Hiltons'] life or anything," Haylie said.

And speaking of Paris Hilton ...

"I knew you were going there, I knew it!" Haylie interrupted -- "there" being the battle between Haylie and Paris over the rights to a song called "Screwed" that both have recorded (see [article id="1489998"]"Leak Complicates Paris/ Haylie Fight Over Who Gets 'Screwed' "[/article]).

"I don't know, there's all sorts of stuff going on [with "Screwed"]," Haylie said, scooting around the question. "Right now we're still recording and writing. I didn't sign the papers with Hollywood Records [Hilary's label]. ... We're just working on some acting stuff right now and kind of deciding what we're going to do with the music."

Along with "Material Girls," which will film in January, Haylie is shooting the indie "Dishdogz." In a perfect world, she would also do a sequel to the surprise hit "Napoleon Dynamite," although there are no plans as of yet.

"A sequel would be awesome," she said. "It's my favorite movie. We threw a big Halloween party, a couple of my girlfriends and I, and people came dressed up as Napoleon and Pedro and Summer and I turned around and was like, 'Oh my God, you came dressed up as me!' It's kind of crazy."

Hilary and Haylie also just finished voicing "In Search of Santa," which will be released directly to video on November 23. In the animated movie, the sisters play penguin princesses, Crystal and Lucinda, who set out on a journey to find Santa Claus.

Hilary then has "The Perfect Man," with Heather Locklear and Chris Noth, hitting theaters around Valentine's Day.

The former "Lizzie McGuire" star also has a European tour in the works for the first part of 2005 and will hit the States in the summer. In the meantime, she's performing at several radio station-sponsored holiday shows and will drop the second single from her recently released self-titled album.

"I really want 'Weird' [to be the next single], I like that," Hilary said. "We haven't shot a video or anything yet, so I gotta hurry."

On Tuesday, Hilary and Haylie joined Clay Aiken, Randy Jackson and other celebrities in making cement handprints that are being auctioned off on eBay to benefit Ronald McDonald House Charities. The event was part of the third annual World Children's Day. ([article id="1493702"]Click for photos of Hilary, Haylie and Clay at World Children's Day.[/article])

"If you go in and get anything that's a value meal, anything with a number, 15 cents of that goes to a Ronald McDonald House charity," Hilary said. "It's so easy to give."