Klazina Petronella Koster, born circa 1777 (?), died on February 18, 1828, aged approximately 51 years.

Klazina was married to
Martinus Overvest, born circa 1779 (?), died on July 21, 1833, aged approximately 54 years.

• 1 : Helena Petronella Overvest, born in Delft on October 15, 1822.
  Helena was married in Leeuwarden on August 3, 1851, at the age of 28 to Bauke Wybes Feenstra (aged 38 years), born in Irnsum on July 5, 1813, son of Wybe Baukes Feenstra (merchant) and Romkjen Klazes Wouters (grocer), Battery sergeant major 3rd Regiment Artillery and superintendant St. Anthony's home.