| Name | Role | Place | Source | |
|---|---|---|---|---|
| Willem Frederik Seyn | Deceased | 1876 | Leiden | |
| Willem Hubert Caspar Antonie Seyn | Registered | 1872 | Roermond | Population register |
| Willem Hubert Casper Antonie Seyn | Military | Studbooks | ||
| Willem Hubert Casper Antonie Seyn | Father | 1970 | Breda | Civil registration deaths |
| Willem Hubert Casper Antonie Seyn | Father | 1970 | Breda | Civil registration deaths |
| Willem Karel Seyn | Decorated | 's-Gravenhage | Registration honors | |
| Willem Karel Seyn | Registered | 1905 | 's-Gravenhage | Population register |
| Willem Karel Seyn | Registered | 's-Gravenhage | PoW cards | |
| Willem Pieter Antonie Seyn | Military | Studbooks |
Find your ancestors and publish your family tree on Genealogy Online via https://www.genealogieonline.nl/en/