Dave, my brother-in-law, has just died after living with Parkinson's for several decades. What follows below is not the whole story of Dave by any means, just the bits I remember best. (We're remembering him by suggesting donations to Parkinson's UK.)
The Parkinson's was with him for several decades. It was a few years before it was properly diagnosed and he was able to get the appropriate treatment. He lived with it for many, many years. He had a life and he lived it well. He continued for many years to cycle into college. He went on working, researching, teaching, contributing and enjoying his food. He dabbled in many things. Well, when I say dabbled, he put a lot into it – a railway line in the garden, astronomy – proper astronomy with a telescope on wheels, sailing, a human mix of joy in nature with scientific precision. And the curiosity of the researcher never went away. After retirement and with his Parkinson's well advanced, he got interested in a problem somebody told him about to do with yachts, keels and sailing positions. There must be a mathematical model for this, he thought, and began to examine the problem with a computer programme. I never heard whether he solved it, but for him I don’t think solving it was ever the main motive. He just liked messing around with things and with numbers and seeing what they would do together.
He also continued with his life the way he always had done, not letting the Parkinson's get in the way of that. There were meals out and holidays, even cruises. I would get pictures from time to time which I might have thought were designed to make me jealous if there was an ounce of malice in either Dave or Julia. Nearly every picture we have of him involves a sun hat. He would cook; and when I say cook, I mean cook, not just opening tins, but starting from scratch. I remember him, with a considerable tremble, cooking butternut squash soup, then sashaying across the kitchen with a pan full of boiling soup, everyone else diving for cover, and Dave filling the bowls from the pan without spilling a drop.