The words I never wrote : [a novel]

"New York, present day: Juno Lambert buys a 1931 Underwood typewriter that once belonged to celebrated journalist Cordelia Capel. Within its case she discovers an unfinished novel, igniting a transatlantic journey to fill the gaps in the story of Cordelia and her sister and the secret that lies between them. Europe, 1936: Cordelia's sister Irene marries a German industrialist who is a Nazi sympathizer. Irene doesn't dare admit what her existence...