Sijtje Vriend was born 5 February 1803 in Venhuizen, North Holland, Netherlands to Pieter Vriend (1770-1837) and Marijtje Stam (1771-1837) and died 21 April 1837 Hoogkarspel, North Holland, Netherlands of unspecified causes. She married Pieter Koopman (1801-1850) 25 April 1824 in Venhuizen, North Holland, Netherlands.
Siblings
| Name | Birth | Death | Joined with |
| Maartje Vriend (1791-1847) | 7 November 1791 Venhuizen, North Holland, Netherlands | 3 September 1847 Blokker, North Holland, Netherlands | Jan Karsten (1793-1861) |
| Gerrit Vriend (1792-1793) | |||
| Trijntje Vriend (1793-1793) | |||
| Jan Vriend (1794-1795) | |||
| Trijntje Vriend (1796-1827) | 31 January 1796 Venhuizen, North Holland, Netherlands | 11 December 1827 Nibbixwoud, North Holland, Netherlands | Petrus Neefjes (1799-1865) |
| Jan Vriend (1797-1863) | 8 October 1797 Venhuizen, North Holland, Netherlands | 16 January 1863 Wervershoof, North Holland, Netherlands | Jantje de Boer (1801-1886) |
| Marijtje Vriend (1798-1827) | |||
| Sijtje Vriend (1803-1837) | 5 February 1803 Venhuizen, North Holland, Netherlands | 21 April 1837 Hoogkarspel, North Holland, Netherlands | Pieter Koopman (1801-1850) |
| Gerrit Vriend (1804-1828) | |||
| Dirk Vriend (1806-1881) | |||
| Jacob Vriend (1809-1832) | |||
Residences
Footnotes (including sources)
| ‡ General |
| ₪ Wedding |
| ¶ Death |