The heavy metal singer, who later became known for his reality show "The Osbournes," performed a retirement concert just three weeks ago.

News of Osbourne’s death comes more than five years after he announced his Parkinson’s disease diagnosis in January 2020.

As the lead singer of Black Sabbath, he helped invent heavy metal. On “The Osbournes,” he presented a comedic counterpoint to his rock ’n’ roll infamy.