Bartholomeus Koster (1867-1918) 
|
Neeltje Sundag (1870- ) |
| Anna Albertina Koster (1886-1887) |
Cornelis Johannes Koster (1888- )  |
| Johannes Koster (1891-1894) |
| Anna Albertina Margaretha Koster (1894- ) |
| Carl Friedrich Helms (1897- ) |
| Neeltje Koster (1893- )
|
