[3] Mary Berg's father was Shaya (Sruel, Stanley) Wattenberg, a local gallery owner in prewar Łódź.

Due to their American connection, prior to the liquidation of the ghetto (Grossaktion Warsaw), the sisters and their parents were detained in prison in Pawiak in July 1942.

In January 1943, Mary and her family were transferred to Vittel, a French internment camp for British and American citizens and others who temporarily escaped death.

After their departure, many of the inmates of Vittel, including Mary's roommate, were transferred back to German-occupied Poland to their deaths at Auschwitz.

[9] It was republished in 2006 by Oneworld Publications as The diary of Mary Berg: growing up in the Warsaw ghetto (ISBN 1851685855/ISBN 978-1851685851), and again on April 1, 2009.

Her known relatives, descended from her sister, Anna, who married a pathologist, Leon Williams Powell Jr. and had four children,[4] have either refused to provide or have disclaimed any new or additional information about Berg, so little is known about her years in the United States.

[15] Her identity was discovered after her death when a part time antiques dealer bought her scrapbook at an estate sale because he was interested in her photos of aircraft.