Who: Taylor Swift, Philanthropist

Day Job: Singer-songwriter.

Passion Project: Several years ago, Taylor Swift stumbled onto a blog by Maya Thompson, a mother in Phoenix, documenting the life and death of her son Ronan, who had the childhood cancer neuroblastoma. "It absolutely devastated me," recalls the 24-year-old. "She had to watch her 3-year-old die and was able to do nothing about it. I woke up in the middle of the night with a verse about his story."

Hit Parade: Swift's hit song "Ronan" is heartbreakingly beautiful—a gift to Thompson and all grieving parents—and, because Swift chose to donate her royalties to cancer charities, an important fundraising vehicle. It was also the spark that prompted Swift to devote herself to a head-spinning array of causes.

Proof Positive: She's given well over a million dollars to disaster-relief efforts and $4 million to create a music-education center at the Country Music Hall of Fame and Museum in Nashville, Tennessee, which gives children a chance to try out musical instruments, often for the first time. (When the center was low on guitars, she dropped by with 13.)

Extra Credit: Swift engages in acts of everyday kindness you can't put a price on. She makes frequent, impromptu visits to children's hospitals on tour, spending hours talking with patients about music and life and love. "It makes me feel like I'm contributing to this world that has given me so much, but has taken so much from other people," she says. "Acknowledging that is important to me."

Get Involved: CountryMusicHallofFame.com

Related: 19 Other Women Who Are Changing the World

Photo via Peter Hapak

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