The tragic story of acclaimed cellist Jacqueline du Pré (Emily Watson) is one I was already familiar with, but I had no idea that her sister Hilary (Rachel Griffiths) was also an accomplished flautist nor that there was allegedly a bit of fluidity amidst their marital relationships. Initially, both are encouraged when they are very young by parents (Celia Imrie and Charles Dance) to practice hard and to play to…