Kelly Osbourne was by dad Ozzy Osbourne's side throughout his battle with Parkinson's disease. The Black Sabbath frontman revealed during a 2020 appearance on Good Morning America that he was diagnosed with the illness the previous year. Kelly was by her father's side for the sit-down and opened up about Ozzy's condition. "The hardest thing is watching somebody that you love suffer," she reflected. After announcing his diagnosis, Ozzy battled more health issues and underwent multiple procedures.