Olivia Wise, a 16-year-old girl with an inoperable brain tumor who became known for covering Katy Perry’s hit, “Roar,” died Monday. “She died peacefully in her home surrounded by the extraordinary love of her family,” a family statement said, according to CNN. Her mother also told CNN that Olivia didn’t want people to cry at her funeral, but rather to celebrate her life.

Wise chose to record herself singing “Roar” in September – after she discovered there were no more treatments available to save her life. The video, which depicted her recording the song in her wheelchair, was uploaded to YouTube in October and even reached Katy Perry herself. The 29-year-old musician responded to Wise’s cover with her own video, where she thanked the teenager and offered her words of encouragement: “I was very moved and you sounded great,” she said in her video. “I love you. A lot of people love you and that’s why your video got to me.” Wise’s video received over one million hits on YouTube and raised some $77,000 for the Liv Wise Fund, which was started in her name to support brain tumor research.

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

Wise has been battling for her life for nearly two years, after she was diagnosed with an aggressive form of brain cancer in January 2012. “Every day, she wished for a cure, and rarely succumbed to negative thoughts,” Wise’s mother told CNN. “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.”