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(Yahoo!) - Olivia Wise, the 16-year-old girl who roared despite a fatal diagnosis and captured the world's heart when she recorded a moving cover of Katy Perry's hit song "Roar," died Monday.

Wise had an inoperable brain tumor, which was discovered in January 2012 after she had a seizure. The teenager refused to let her diagnosis get her down, and realized her dream of going into a recording studio to cover Perry's uplifting song.

"I got the eye of a tiger, a fighter, dancing through the fire / 'Cause I am a champion and you're gonna hear me roar," Wise sang in a soft, angelic voice.

The video went viral and has been viewed more than 1 million times. One of those viewers was Perry herself, who responded to Wise with a heartwarming video of her own. "I was very moved and you sounded great," Perry said in her clip. "I love you. A lot of people love you, and that's why your video got to me. It moved everybody that saw it. Keep roaring!"

Wise remained optimistic throughout her ordeal, her mother told CNN. "In many ways, Olivia has lived a shortened, but full life," she said, adding that she rarely complained about her grave condition. "Every day, she wished for a cure, and rarely succumbed to negative thoughts."

"She died peacefully in her home surrounded by the extraordinary love of her family," her family wrote in a statement to CNN, adding that she didn't want people to cry at her funeral, but instead asked that they celebrate her life.

This philosophy is evident in the video, which Wise leaves behind as comfort and inspiration for her grieving family and friends. It also serves as a catalyst to support brain tumor research through the Liv Wise Fund. So far, more than $115,000 has been raised in Wise's name for cancer research and to support children living with brain tumors.

After hearing the news of Wise's death, Perry tweeted a lovely message: