Irene Hizme and her twin brother, Rene Slotkin, were born in Czechoslovakia and were only four years old when they were taken with their mother to Theresienstadt. Shortly afterward, they were sent to Auschwitz, where they were separated. They never saw their mother again. They survived for almost three years in Auschwitz where they were experimented on by Josef Mengele as part of his twins research. Irene later recalled:

"I remember the first time I saw Mengele he was wearing green, dark green. And I remember his boots. That was probably the level my eyes were. Black, shiny boots. He was asking for twins, twins ..."

"The first time we went to the infirmary, he took blood. It was very painful ... They gave me injections in the arm and the back, and X-rays. I'd be extremely sick for a while."

After the war, Irene was adopted by a family on Long Island and spent several years tracking down Rene, who was still in Europe. In 1950, the family was finally able to bring him to the United States and reunite the twins. And both got married with children.