Miley Cyrus (in green) with the Gilyeat family, <EM>Extreme Makeover: Home Edition</EM> Miley Cyrus (in green) with the Gilyeat family, Extreme Makeover: Home Edition

Hannah Montana star Miley Cyrus doesn't have much time for go-karting these days, but it's something she's considering after her experience on Extreme Makeover: Home Edition (Sunday at 8 pm/ET, ABC). During a surprise backstage visit arranged by the show in San Diego recently, the four breathless children from the Gilyeat family asked Cyrus to join them sometime for a spin around the track back home in Kansas City, Kansas.

''The kids were so cute and excited, I thought, 'I gotta check my schedule,''' says Cyrus, who went one better and performed for the family in the episode that airs this week. Cyrus, after all, is a huge EM:HE fan and didn't blink when she was asked to guest-star. ''I love the show's message. No matter how sad or negative the family's situation is, everyone comes out smiling.''

That's certainly the case with the Gilyeats. Daniel Gilyeat and his children faced tremendous challenges last year after the Marine dad lost his leg above the knee when a bomb hit his truck in Iraq. It was Daniel's second tour of duty, and he returned home to a marriage that couldn't survive the stress. Despite the setbacks, Daniel was up on a prosthetic leg 25 days later and counseling other injured soldiers. ''This is a guy with an indomitable spirit,'' EM:HE executive producer Denise Cramsey says. ''He managed to work through his own struggle in order to help people worse off, all while fighting to keep his kids safe.''

Now the children — Alexis, 9; Victoria, 8; Danny, 6; and Nicholas, 4 — are safe and comfortable. In seven days, a home with uneven floors and doors too small to accommodate a wheelchair was demolished to make way for a 2,850-square-foot four-bedroom Zen oasis. ''We wanted him to have a home that was masculine but also calming,'' says Eduardo Xol, the lead designer on the project. That explains the bamboo, Chinese antiques and other Asian touches, but, c'mon, this is Extreme Makeover! ''OK, so we gave the boys a bed made out of a monster truck that lights up,'' Xol says. Adds Papa Gilyeat, ''They even put a horn in it that sounds like there is a semi in the room. I quickly figured out how to unwire it, but my 4-year-old figured out just as quickly how to rewire it.''

Not that Gilyeat is complaining. ''I feel like I'm babysitting somebody else's house,'' he says. ''I just look at it and gasp. The gutters are made of copper, but to me it looks like they're made of gold."

Extreme Makeover is nearing the end of its 50-state marathon; upcoming dream-house recipients include a Louisville, Kentucky, man who was born blind and unable to use his arms or legs, yet plays in a marching band. Country superstar Toby Keith is set for a guest appearance, and the season ends with a return visit to Hurricane Katrina-ravaged Louisiana — all of which should keep addicted viewers like Cyrus glued to the tube. ''I can't get enough of the show,'' she says. ''It's a thrill to watch so many people get the help they deserve.''

Watch full episodes of Extreme Makeover: Home Edition in our Online Video Guide.

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