Karol Wojtyla as a seminarian in Poland. Wanda Poltawska was 17 when the German army overran her country. She was 18 when Nazi doctors used her as a guinea pig for experimental surgical techniques at the Ravensbrück concentration camp. She studied medicine and psychiatry in the difficult years after the war, trying to understand how human beings could sink to such barbarism. But when she was stricken with cancer at age 40, a still greater tragedy loomed for her and her young children. Then two saints stepped in. The young bishop Karol Wojtyla wrote personally to St. Pio of Pietrelcina...