I am researching a Robert Buchman, Jewish, born in Russia. His name is sometimes spelled Buckman in the census or in newspaper articles. His immigration date is 1892. He married Sarah Zalk in 1898. They lived in Duluth MN, moving to NYC in 1919. Their children were Moses Robert (pediatrician, Scarsdale NY), Sidney Robert (famous screenwriter), Marian Lamm (husband Herbert, professor of philosophy at University of Chicago), and Harold (screenwriter).
Does anyone have information on Robert Buchman's ancestry or siblings?