Dr. Mengele

During the 1930's and 1940's, Dr. Mengele, a German scientist, began doing eugenics experiments on twins. This is mentioned briefly in the book. These experiments were part of the Hitler/Nazi regime and were really awful. If you would like to learn more about these, click here to read a wikipedia article. (Warning: If you are prone to queasiness or easily upset, this might not be for you.)