I have 2 books: Lucky Man and Always Looking Up by Michael J Fox. I have tons of book suggestions, because I love to read, but if I had to choose an important book it would be these two. They are about Michael J Fox's life, rise to fame and then diagnosis with Parkinson's Disease. Through it all he stays optimistic. He has built a life with his wife and four children. He had some of those children after his diagnosis. It's just a great and inspiring read.
My Grandpa lived the last years of his life with Parkinson's, and although it is very different than the early onset that Michael J Fox was diagnosed with, I have still seen first hand what the disease does to a person. I think that Michael J Fox has done a great job bringing attention to the disease and raising money for finding a cure.