Sixteen-year-old Olivia Wise covered Katy Perry's "Roar" and got over a million YouTube views since October. She died on Monday of inoperable brain cancer.



Perry heard about Wise's passing and took to Twitter to remember her:

Olivia Wise, I can hear you singing with the angels now. Your spirit & strength has inspired me & so many others... May you rest in peace.

— Katy Perry (@katyperry) November 26, 2013

Wise was in a wheelchair in a recording studio, singing the song's encouraging lyrics.

"She couldn't walk or stand, she didn't have her full breath or the energy she used to, and she was managing her new pains and new limitations," the video's YouTube description says. "While her physical condition was rapidly fading, her spirit remained untouched."

Wise got to see Perry's recorded message to her in October:



Wise's rendition of "Roar" is available to The Liv Wise Fund, which was set up to raise money for brain cancer research.