The young-adult novel by Garrison Keillor and Jenny Lind Nilsson gets a lively update in this Showtime feature about an unusual family in Sandy Bottom, Wisconsin. The Greens share musical aspirations, but daughter Rachel (Madeline Zima), a talented violinist, is the one most likely to achieve them. Norman (Tom Irwin) is a dairy farmer and Ingrid (Glenne Headly) is a choir director who abandoned the piano when she married and settled down, but the Greens are a happy family, for the most part. The...