Selman Katz and Sara Reich each moved to Dortmund in the early 1920s. Before their marriage, Selman Katz lived in Leopoldstrasse, Sara Reich on Neuer Graben. At the end of 1923, Sara Reich moved in with Selman Katz in his flat at Adlerstrasse 36. The couple married on 13 December 1923.
Selman worked in various jobs, including as a labourer, a fitter and a merchant. Before her marriage, Sara Katz worked as a household help.

In the following years, they had three children: Benno Katz (born 24 November 1924), Heinz Katz (born 16 November 1927) and Kläre Katz (born 30 May 1937).

On 28 October 1938, in the course of the so-called “Polish action”, the family were expelled from Germany and deported to Bentschen on the Polish border.
The family had already been making attempts in previous years to emigrate to Palestine, France or the USA. In Poland, they at least succeeded in saving the lives of the two sons, Benno Katz and Heinz Katz, by arranging for them to go on a child transport to England. According to the reports of the surviving sons, the parents and their daughter then went to Warsaw, where they were sent to live in the ghetto. And all trace of them ends there. Whether they were already killed in the ghetto or were deported to one of the extermination camps is not known.