Entertainment Music Katy Perry Leaves 8-Year-Old Australian Fan Battling Brain Tumor in 'Awe' After Home Visit Grace is "definitely walking on cloud nine this morning. It's definitely given all of us a bit of a lift," her mother, Marie Moores, said By Emily Zauzmer Published on August 1, 2018 12:25 PM Share Tweet Pin Email Photo: Katy Perry/Instagram When an Australian fan’s health woes kept her from Katy Perry‘s concert, Katy Perry came to her instead. Grace Moores, 8, who is fighting a brain tumor, was gifted tickets to Perry’s Witness: The Tour concert in Adelaide for her birthday, according to The Advertiser. But she had to miss the show because of an operation last week. Her sister, Tiana Moores, 16, used Twitter to reach out to Perry and share Grace’s story, noting that Grace “has been battling all year” and has “been Katy’s biggest fan since she was 3.” More than 20,000 retweets helped the 33-year-old pop star hear about Grace. On Tuesday, Tiana’s online outreach paid off. Perry spent an hour with Grace, her parents, and her four siblings at their home in Banksia Park. “When Katy arrived out the front, Grace was a bit shell-shocked. She was just in awe. The smile on her face was just priceless,” Grace’s mother, Marie Moores, recalled to The Advertiser. “She’s definitely walking on cloud nine this morning. It’s definitely given all of us a bit of a lift.” Marie said that Grace gave Perry a tour of her bedroom and that Perry played three songs of Grace’s choosing with two band members. The BBC reports that Grace selected “Roar,” “Firework,” and “Chained to the Rhythm.” Katy Perry Had ‘Situational Depression’ from Negative Reaction to Witness Album “Katy is the most down-to-earth, genuine person you could meet,” Marie continued to The Advertiser. “Just for someone like her to take that time out of her day to make all Grace’s dreams come true has just put a whole new spin on the really crap year we’ve had so far.” After the visit, Tiana tweeted, “GUYS WE DID IT! @katyperry just visited grace! She’s [truly] amazing and such a sweet person this was [truly] amazing!” RELATED VIDEO: Katy Perry and Orlando Bloom Step Out for Sexy Date Night in London Tiana also posted a silly selfie that Perry took on her Snapchat. Katy Perry Jets to London for 24 Hours to Enjoy Quickie Date Night with Orlando Bloom Many celebrities have used their star power to bring cheer. Last month, Gal Gadot dressed up as Wonder Woman to meet patients at a children’s hospital in Falls Church, Virginia, and Ryan Seacrest and Camila Cabello stopped by the Children’s Hospital of Philadelphia. And Madonna brought all six of her children to Malawi to visit the hospital she opened a year ago.