Jacob Sijm was born 7 March 1775 in Andijk, North Holland, Netherlands to Jan Sijm (1739-1822) and Antje Knuijsen (1737-1825) and died 2 November 1840 Andijk, North Holland, Netherlands of unspecified causes. He married Grietje Diggelom (1776-1853) 1804 in Grootebroek, North Holland, Netherlands.
Children
| Name | Birth | Death | Joined with |
| Antje Sijm (1804-1873) | |||
| Neeltje Sijm (1806-1888) | 9 February 1806 Wervershoof, North Holland, Netherlands | 18 February 1888 Andijk, North Holland, Netherlands | Jan Laan (1802-1880) |
| Jan Sijm (1808-1874) | 8 February 1808 Bangert, Andijk, North Holland, Netherlands | 1 May 1874 Wervershoof, North Holland, Netherlands | Elisabeth Dekker (1811-1850) |
| Pieter Sijm (1809-1839) | |||
| Maartje Sijm (1811-1890) | 2 June 1811 Bangert, Andijk, North Holland, Netherlands | 1 January 1890 Wervershoof, North Holland, Netherlands | Dirk Meester (1811-1888) |
| Simon Sijm (1813-1842) | |||
| Aafje Sijm (1815-1847) | |||
| Elisabeth Sijm (1817-1900) | |||
| Volkert Sijm (1819-1859) | 2 April 1819 Andijk, North Holland, Netherlands | 19 April 1859 Wervershoof, North Holland, Netherlands | Grietje Bot (1830-1903) |
Footnotes (including sources)
| ‡ General |
| Ω Birth |
| ¶ Death |