Jacobus Willemsen de Bock, born in Woudsend on January 7, 1821, son of Stephanus Jacobus de Bock and Trijntje Michiels Tromp.
Jacobus was married in Wymbritseradeel on May 7, 1842, at the age of 21 to
Neeltje Aukes Cnossen (aged approximately 22 years), born circa 1820 (?).