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From Make-A-Wish to St. Jude Children's Hospital, the stars of High School Musical have brightened the lives of children across the country. "It's a very humbling experience," Zac Efron tells PEOPLE of working with the Make-A-Wish children, all of whom are coping with life-threatening medical conditions.
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A ROYAL TOUCH
Prince Harry is following in his mother's footsteps, launching his Sentebale charity (which means "Forget Me Not") benefitting Lesotho, Africa's impoverished orphans, in 2006. When asked if his mother Diana – who famously hugged AIDS patients – would have been proud, Harry smiled and said, "I hope so."
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In 2007, Brad Pitt launched Make It Right, a campaign to help rebuild New Orleans's Lower Ninth Ward, which was devastated by Hurricane Katrina in 2005. "My hope is that we can grow this thing," he said of his effort to build 150 homes for displaced families.
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In the wake of the Sept. 11 attacks, stars including Tom Cruise, Meg Ryan, Madonna and others came together in Los Angeles, New York City and London to sing, speak and staff phones in an effort to raise millions for the United Way's effort to assist disaster victims and their relatives.
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From Julianne Moore to Julia Roberts, stars use their fame to shed light (and raise money) for the causes closest to their hearts. "The only thing celebrity is good for is to bring attention to things that need attention," says Moore, who raises awareness for the genetic disorder Tuberous Sclerosis Complex.
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Jessica Simpson embarked on a 10-day trip to Kenya in 2005 as goodwill ambassador for Operation Smile – an international charity that provides free reconstructive surgery to kids born with facial deformities. "It's crazy, to go there to bring blessings to these kids," she said, "and they end up blessing you more."
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Though her life was cut short in 1997, Princess Diana's legacy lives on thanks to her tireless efforts on behalf of those less fortunate. "She's gone, but she's like the gift that keeps on giving," says a benefactor. "Her touch goes a long, long way."