Jungreis was born and raised in Szeged, Hungary on April 27, 1936, to Avraham and Miriam Jungreis. Her two brothers, Jacob and Binyamin, both became rabbis. Her father was an Orthodox rabbi and operated a little "shtiebel" in the city, Abraham Jungreis was deported with other Jews from Szeged in a cattle car bound for Auschwitz. However a relative who worked for Rudolph Kastner's office arranged that when the train from Szeged passed through Budapest the cattle car was opened and the entire Jungreis family was transferred onto the so-called Kastner train, which after a journey of several weeks and a diversion to the Bergen-Belsen concentration camp in Germany, delivered its 1,670 passengers in Switzerland.