Ruth Gruener was born Aurelia Gamser in 1930s Poland. Ruth and her parents survived the Holocaust by hiding in the homes of gentile families. After World War II was over, Ruth and her family moved to the United States, where Ruth tried to start an ordinary teenage life in Brooklyn. Ruth married Jack Gruener, another Holocaust survivor, with whom she lived in Brooklyn until Jack's passing in 2017. They have two children and four grandchildren. Ruth works as a docent at the Museum of Jewish Heritage in downtown Manhattan and travels all over the country to speak to schools about her and Jack's experiences in the Holocaust.