Most people are more interested in ancestors than their siblings, but records of the siblings can contain vital clues.
For example, death duties files (memories van successie) of siblings who died without children can show that nieces and nephews or more distant relatives inherited. The death duties files can reveal complex family relationships, especially in the case of an elderly person who died after their siblings.
Another tip is to always check the marriage supplements of marriages of siblings, especially the younger siblings. If they married after their parents had died, the supplements may contain extracts of their parents’ death records and even of the grandparents.
Group of cousins, all grandchildren of Cornelis Trouw and Maria Gommeren
About Yvette Hoitink
Great information. Another advantage in researching siblings is that first cousin (and second cousin) marriages become obvious. In some families, especially those in smaller communities, many first and second cousin marriages are noted, and in some cases — even step cousin marriages can be be identified. In one family step children married siblings. I was surprised at the number of first cousin marriages found in some of my families.