Jack Osbourne, the son of Black Sabbath frontman Ozzy Osbourne, has said he’s been diagnosed with multiple sclerosis. The diagnosis came after he began losing vision in his right eye, the 26-year-old revealed in an interview with Britain’s Hello! magazine. “I was just angry and frustrated and kept thinking, ‘Why now?’” Osbourne said of the diagnosis, which came two weeks after his first child, daughter Pearl Clementine, was born. “I got really sad for about two days, and after that I realized being angry and upset is not going to do anything at this point—if anything it’s only going to make it worse,” he said. There is no known cure for multiple sclerosis, an autoimmune disease that afflicts the nervous system.