Pieter Holsteijn, born in Groningen on February 22, 1870, son of Harm Holsteijn (carpenter, carpenter and carpenter) and Grietje Rijkens (maid servant), bediende and bediende.

Pieter was married in Groningen on April 23, 1899, at the age of 29 to
Tjakomina Egberta Kram (aged 26 years), born in Groningen on July 20, 1872, daughter of Derk Kram (warehouseman) and Roelina Werkman.