Leah Smith, the 22-year-old TikTok star from the UK diagnosed with the rare cancer Ewing's Sarcoma, passed away on March 11. Sharing the news of her death on TikTok, her boyfriend Andrew said Leah "will never be forgotten". Ewing's Sarcoma is a rare type of bone cancer that most commonly affects people who are 10 to 20 years old.