New Novel

While working a rewrite of an old story, I discovered that it wanted to be a novel. I have now written some 70 pages of a book with the working title Two Sisters. It has a Holocaust back story, but focuses on a man of a certain age who has his whole life been unsure which of two sisters is his biological mother. Both women were in Auschwitz. One survived and with her husband came to New York and raised the man. The other sister died in the camp. But the man has reason to believe that not only was the one who died his mother, but that his father was the Nazi officer who raped her.