Lea was born in the city of Sombor in northeastern Yugoslavia. When she was 3 years old, her parents divorced and she moved to Vienna with her mother, who taught English and French to Austrian children. Lea enjoyed living in Vienna as a child.
1933-39: Lea returned to Sombor almost every year to visit her mother's relatives. There, she became reacquainted with her younger half-sister, Julia, and her older half-brother, Francis, and would miss them when she returned to Vienna. In 1938, the Germans annexed Austria, and Lea and her mother fled to Budapest, Hungary.
1940-44: In Budapest Lea studied nursing at one of the city's two Jewish hospitals, and she met and married Dr. Tamas Szemere, a pediatrician. Lea was pregnant when Germans troops entered Hungary in March 1944. She and Tamas were deported from Budapest to Auschwitz in a cattle car crowded with 96 other Jews. They traveled without food or water for three days before the train arrived in Auschwitz.
When the train-car door was opened by SS men, Lea lay lifeless on the floor. She had died en route after delivering. The stillborn baby was at her feet. Tamas lay beside them; he had killed himself.