I have new clues!
From the obituaries of Helen Pollock's parents, found in the Youngstown Vindicator newspaper (found at myheritage website), I learned that Helen has 3 sisters and 2 aunts!
Helen Pollock's sisters:
Mrs. [Annie] Simko of Masury, Ohio
Mrs. Joseph of Hartford [Connecticut]
Mrs. Suzanne Ragan of Masury, Ohio (1940 of NYC)
Helen's two aunts (her mother Anna Petrosky's sisters) are:
Mrs. Mary Tarnovich of Brooklyn
Mrs. Susanne Swab in Europe
I also know that when Anna Petrosky died April 23, 1944, she had 12 grandchildren - including Dorothy and Al (Helen's children). Anna's obituary is dated April 24.
Helen's dad Michael Pollock died July 19, 1940 and his obituary is dated July 20.
I know that Helen's sister, Mrs. Simko, has the first name of Annie - because of cards found in Dorothy's scrapbook from "Aunt Annie Simko."