Michael Bolton<\/a>\u00a0was enjoying time with his family in the fall of 2023 when something unexpected happened.<\/p>\n While out for a night of bowling with his kids and grandkids, the Grammy-winning singer, 72, bowled out of turn. Then he did it again. And again.<\/p>\n The incident was \u201csuper weird,\u201d his daughter Taryn recalls in this week\u2019s PEOPLE cover story \u2014 and it turned out to be a major indicator that Bolton was dealing with a serious health issue that would later be diagnosed as glioblastoma, a rare and aggressive form of brain cancer.<\/p>\n \u201cThat was when we were like, \u2018Something\u2019s wrong with his brain,\u2019\u201d Taryn, 45, says. \u201cEverything that happened was weird for him but not super alarming. When you look back at everything together \u2026 We missed so many things.\u201d<\/p>\n At the time, Bolton\u2019s career was thriving. He\u2019d recently performed a number of concert dates, appeared on\u00a0The Masked Singer<\/em><\/a>, released an album in July 2023 and filmed a cameo in the movie\u00a0The Fabulous Four<\/em><\/a>\u00a0that October.<\/p>\n But a performance in mid-November at a charity event on\u00a0Richard Branson<\/a>\u2019s Necker Island was marred by an unusual bout of nausea and balance issues, which Taryn and her sisters Holly, 47, and Isa, 49, chalked up to stress and exhaustion.\\<\/p>\n \u201cIs this stress? Is this sleep?\u201d Taryn remembers wondering. \u201cHe\u2019d been working nonstop that whole time. Traveling, doing shows, doing all of these things. We were like, he\u2019s getting older, he\u2019s tired, he\u2019s stressed out. All of these things we sort of explained in a way, one by one.\u201d<\/p>\n The bowling outing happened just after Thanksgiving 2023, and earlier that same night, Bolton\u2019s family noticed another red flag.<\/p>\n \u201cHe fell out of his chair to the left, which is very unusual. He\u2019s super athletic, and he doesn\u2019t drink,\u201d says Taryn. \u201cSo he fell, and we were like, \u2018What just happened?\u2019\u201d<\/p>\n Over the same weekend, Bolton had a \u201cbad\u201d headache \u2014 and on Monday, he went to the hospital, where an MRI confirmed he had a brain tumor. The tumor was removed in its entirety during surgery, and about a week later, doctors confirmed it was glioblastoma, which affects approximately 15,000 Americans each year, per the\u00a0National Brain Tumor Society<\/a>.<\/p>\n Bolton\u2019s neuro-oncologist, Dr. Ingo Mellinghoff of Memorial Sloan Kettering Cancer Center in New York City, says symptoms of brain tumors often include sudden changes in personality, severe headaches, seizures, coordination issues and muscle weakness and paralysis.<\/p>\n \u201cIf all of a sudden you\u2019re a completely different person, and people are like, \u2018He never gets out of bed anymore. What\u2019s going on? He doesn\u2019t want to do anything\u2019…,\u201d Mellinghoff says. \u201cIf somebody can\u2019t move one part of their body, that\u2019s never normal. Or changes in sensation. When they say, \u2018I can\u2019t feel anything anymore on my right side.\u2019\u201d<\/p>\n Mellinghoff adds that changes in speech patterns can also be a red flag.<\/p>\n \u201cSpeech is pretty sensitive. We all have our speech patterns, and if all of a sudden your friend says, \u2018It sounds so strange, and it doesn\u2019t make sense,\u2019 that is definitely something,\u201d he says.<\/p>\n Still, Mellinghoff says that glioblastoma is very rare.<\/p>\n \u201cIt\u2019s really hard to put out the message of, \u2018If you have a headache, think about brain cancer,\u2019 because that\u2019s so rare,\u201d he says. \u201cMany of these symptoms are very nonspecific, so we have to be careful not scaring everyone.\u201d<\/p>\n For Bolton, treatment has included radiation and chemotherapy, which he finished in October. Because glioblastoma has an extremely high recurrence rate, Bolton undergoes MRIs every two months to ensure his tumor has not returned. His most recent scan, in early April, was clear.<\/p>\n![\"Michael](\"https:\/\/people.com\/thmb\/smaL_ofNrLvjlenTE-LuyH18qic=\/4000x0\/filters:no_upscale():max_bytes(150000):strip_icc():focal(999x0:1001x2):format(webp)\/PEOPLE_MichaelBolton_COVER-b2dd44cc349849f3aeaf3630817ced8a.jpg\")
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