Erna was the second of four daughters. Her religious Jewish parents moved the family to Essen, Germany, in 1905 when Erna was 21. Erna married when she was in her twenties, but the couple had no children and her husband passed away. After living as a widow for some years, Erna remarried to Jacob Unger, a salesman, and together they had two children, Max and Dora.
1933-39: When Hitler became chancellor of Germany in 1933, Jacob went to Amsterdam to explore the possibility of the family settling there. Erna, however, could not part from her sisters, with whom she was very close, and so Jacob returned to Essen. In November 1938, after nationwide pogroms, the Ungers finally fled to Amsterdam. Like some uprooted Jewish refugees in the city, their children were placed in the care of Jewish organizations.
1940-44: The Germans invaded the Netherlands in May 1940. After the occupation, Erna and Jacob went into hiding. After three years they were discovered and arrested, although details of how are unknown. On April 17, 1943, Erna and Jacob were sent to the Westerbork transit camp in the Netherlands. Seven days later they were deported to the Sobibor killing center in Poland.
Erna perished at Sobibor in 1943. She was 59 years old. The only family member to survive was Dora, who in 1940 had been smuggled to England with other Jewish refugee children.