This tree starts with Great-grandfather Berkman as a place holder ,since it is known that Reuven Berkman, the ancestor of our branch had a brother Herschel (perhaps Hirsh or Tsvi Hirsh) Berkman, who was a dayan, a rabbincal judge, in Lithuania. My wife's uncle Herbert Block was named for him and given no second name, since Rabbi Berkman was such a significant person, it would have been disrespectful to add another name to his.
 
1  Great-grandfather Berkman
.  +Great-grandmother
... 2   Reuven Berkman
.......  +Rachel Finkelstein
........ 3   Nachum Motel Berkman
............  +Gittel Leah Bloch
.............. 4   Taube Sarah Berkman b: May 25, 1887 in Sudargas, Lithuania
..................  +Meyer (Meier Yitzchak) Block b: Sep 10, 1886 in Sudargas, Lithuania
.............. 4   Rose (Itte Reisel) Berkman b: abt. 1889 in Sudargas, Lithuania
..................  +Samuel (Shepsel) Slotnick b: abt. 1884 in Russia
.............. 4   Robert (Yossel Reuven) Berkman b: 1892 in Sudargas, Lithuania
..................  +Pauline Shapiro b: 1895
.............. 4   Sarah Devorah Berkman b: 1896
.............. 4   Chaya Merke Berkman b: Unknown
.............. 4   Chaya Rifke Berkman b: Unknown
..................  +Meyer Gutmann
.............. 4   Hoshea Hershel Berkman b: Unknown
..................  +Shule
.............. 4   Isaac (Leizer Yitzchak) Berkman b: Unknown in Sudargas, Lithuania
..................  +Sarah Weinstein b: in Russia
.............. 4   Rae (Rachel) Berkman b: Unknown
..................  +Joe Lapidus
.............. 4   Saul (Shlomo Meier) Berkman b: Unknown
..................  +Leah
.............. 4   Sheyne Perke Berkman b: Unknown
........ 3   David Solomon Bergmann
.............. 4   Abraham Bergmann
.............. 4   Bernard Bergmann
.............. 4   Jacob Bergmann
........ 3   Israel Jashel Bergmann
.............. 4   Robert Bergmann
.............. 4   [1] Herman (Yaakov Hirshl) Bergman b: abt. 1887 in Schirwindt, East Prussia
..................  +Unknown
..............  *2nd Wife of [1] Herman (Yaakov Hirshl) Bergman:
..................  +Bella Fruman b: abt. 1898 in Sakiai, Lithuania
.............. 4   Ludwig Bergmann
.............. 4   Ida Bergmann
.............. 4   Clara Bergmann
.............. 4   Albert Bergmann
.............. 4   Lina Bergmann
... 2   Herschel Berkman
... 2   Riva Berkman
.......  +Mr. Finkelstein