Get your Kleenex ready. A terminally ill teenage girl sang 'Roar' by Katy Perry, it went viral, and, well, yeah. It's heartbreaking and inspiring at the same time.

16-year-old Olivia Wise, suffering from an inoperable brain tumor, belted out the tune, and her loved ones made her Internet famous for it.

"Olivia is a fighter and has gone through the fire," her cousin wrote on YouTube. "In fact, she was going through the fire while she recorded this song, but you wouldn't know it, because she was dancing right through it."

"Her health is really bad, she's at the end," another Jeff Kassel told CNN. Still, Wise is keeping a positive attitude. Her mom explained, "She is still conscious at times and taking it all in." "Every day, she wished for a cure, and rarely succumbed to negative thoughts ... To tell the truth, her diagnosis didn't change her personality. It only enhanced it. She took the news in a mature, reasonable, responsible way. ... Even in the most difficult moments, she managed to bring laughter and friendship to all that were caring for her."

The video eventually made its way to Perry herself, who sent her own video to Wise and her family.

"You sounded great," Perry said, visibly moved. "I love you. A lot of people love you. ... Keep roaring."

Watch Katy Perry's Video for Olivia Wise

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