Marczewski was diagnosed with breast cancer in 2017, and declared cancer-free in July 2018. Her cancer recurred in 2019, and she was given three to six months to live, but she was again declared cancer-free in 2020. Prior to her America's Got Talent audition, Marczewski was told that the cancer had metastasized to her lungs, spine and liver. With only a 2% chance of survival, she gave health updates on CNN and social media. At the age of 31, Marczewski died from the disease on February 19, 2022. She was surrounded by family in her San Clemente residence. The AGT judges and host released condolences on social media. A celebration of life, which was live streamed, was held at Cornerstone Church in Ohio on March 4, 2022.