Family #78 in the 1767 Grimm census.
Family #153 in the 1775 Grimm census.
Family D-24 in the appendix of the 1798 Grimm census.
Heinrich Heinz was born about 1729 in the area around Zweibrücken, Germany. He married widow named Katharina Klein, although it's unclear if he married her in Germany or in Russia. Together, they had no children by the time of the 1767 Grimm census, but she had a son, Wilhelm Klein, who lived with the family.
1767 Grimm Census 
Also living with the couple but listed in a separate entry were two orphans: 
Also living with the couple but listed in a separate entry was Katharina Klein Heinz's son, Wilhelm Klein. 
By 1775, Katharina Schwarz was no longer living with the couple, but she was not yet married to Kaspar Hepp. The couple had taken in another child, Wilhelm Klein, who may have been as young as 12 when he came to live with them.
1775 Grimm Census 
Klein and Schwartz was Heinrich Heinz's step-son, but Schwartz was adopted into the home after the deaths of their biological parents. Valentin Schwarz matches one of the orphans he and his wife had living with them in 1767. It was probably easier to refer to Valentin Schwartz as family member, rather than to keep on calling him an orphan.
According to the 1798 census, Heinrich paid his debts, after which he and his family moved to Sarepta, a colony formed by Moravians.  The record specifically says family, so one or both of the young men taken in by the couple may have also moved to Sarepta.
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