Harm married Rijzinga Petronella on 21 Jul 1906 in Usquert. Petronella (daughter of Rijzinga Jakob and Danhof Grietje) was born on 31 Mar 1886 in Usquert; died on 15 Oct 1983 in Groningen; was buried in Noorderbegraafplaats Groningen. [Group Sheet]

1. Staal Grietje was born on 16 Aug 1908 in Usquert.
2. Staal Jakob Jan was born on 4 Nov 1909 in Roden.
3. Staal Stientje was born on 4 Nov 1909 in Groningen.
4. Staal Steven was born on 18 Mar 1912 in Groningen.
5. Staal Harm was born on 27 May 1919 in Groningen; died on 15 Aug 1972 in Groningen.