Alice was born in Prague, Austria-Hungary, along with her twin sister Mariana. She married musician Leopold Sommer in 1931 and had a son, (1937-2001). After the invasion of Czechoslovakia, most of her family and friends emigrated to Palestine via Romania, including Max Brod and brother-in-law Felix Weltsch, but Herz-Sommer stayed in Prague. In 1942, her ill mother Sophie was killed. A year later, Herz-Sommer, her husband and son were sent to the Theresienstadt concentration camp. Herz-Sommer played at music concerts in the camp along with other musicians. Leopold was later sent to Auschwitz and though he survived the camp, died at Dachau in 1944. After the Soviet liberation of Theresienstadt in 1945, Herz-Sommer emigrated to Palestine to be reunited with her family. She lived in Israel until emigrating to London, United Kingdom with her son in 1986.