After the outbreak of World War II, her mother Lonni Wheeler Sanger, born Louise Wernicke in 1891 in Berlin, relocated to the United States with Helen and her two sisters, Charlotte and Eleanor.
She was appointed the Chief Librarian of the Library in 1978, taking over the position from Mildred Steinbach.
[2] She also managed "The Spanish Project," the Library's response to the United States government's general request to American research institutions to initiate "major international projects" that would strengthen ties between the United States and Spain in preparation for the Columbian Quincentenary in 1992.
[3] The project initiated by the Library had three aims, all of which were supervised by Sanger: to complete an annotated checklist of more than 7,000 Spanish artists active between the fourth and twentieth centuries; to hone the skills of graduate students from Spain and the United States in art-historical research and introduce them to database creation; and to augment considerably the Photoarchive's holdings in Spanish art.
Helen and Eleanor had an older sister, Charlotte (Lonni) Sanger Ward, who died on August 12, 1955.