Sir Billy Connolly says he's suffered ‘serious falls’ following his Parkinson’s diagnosis.The legendary comic first went public about being diagnosed with the disease in 2013.Parkinson’s is a condition in which parts of the brain become progressively damaged over many years, as per the NHS.Symptoms of the disease include involuntary shaking of body parts, slow movement and stiff and inflexible muscles.Connolly said he was ‘finished with stand-up’ in 2020 and explained to Sky News: “It was the first thing I was ever good at and I'm delighted and grateful to it.“The Parkinson's has made my brain work differently and you need a good brain for comedy. Everything you say should have five or six alternatives behind it.” Talking with his wife Pamela Stephenson, he told The Guardian about the evolution of his diagnosis.“It’s very difficult to see the progression exactly, because a lot of things come and go,” Connolly explained.“Recently I’ve noticed a deterioration in my balance. That was never such a problem before, but in the last year that has come and it has stayed."For some reason, I thought it would go away, because a lot of symptoms have come and gone away.”