| Father | Math Poster (1860 - 1910) |
| Mother | Agnes Brausen (1870 - 1948) |
| Sibling | Olivia Poster (1892 - 1969) |
| Sibling | Martina Genevieve Poster (1893 - 1979) |
| Sibling | Agnes Margaret Poster (1894 - 1977) |
| Sibling | Martin J. Poster (1896 - 1975) |
| Sibling | John P. Poster (1898 - 1964) |
| Sibling | Henry P. Poster (1899 - 1976) |
| Sibling | Mathias Andrew Poster (1900 - 1963) |
| Sibling | Joseph A. Poster (1902 - 1980) |
| Sibling | George Henry Poster (1903 - 1975) |
| Sibling | Alfred P. Poster (1905 - 1963) |
| Sibling | Daniel Poster (1907 - ) |
| Sibling | Frederick Paul Poster |
| Sibling | Hubert J. Poster (1909 - 1991) |
| Sibling | Laura S. Poster |