What would have happened to her if her secret was revealed?
"They would take me to the Nazis, and I would be killed," said the 82-year-old Holocaust survivor who was the special speaker at California State University, Bakersfield on Wednesday evening.
A large standing-room only crowd turned out to hear the story of this woman who also lost her parents, two sisters and a brother to Nazi atrocities.
"The Polish people were against the Jews. They took our possessions, and they didn't want us alive anymore," said Greenstein.
A few Poles however did help hide Jews and keep them safe from the Nazis, she said.
Greenstein shared her story of grit and survival as part of the annual CSUB Days of Remembrance, which is meant to educate and expose the public about the Holocaust.