| Name | Relationship with Natalie Seiwell | Civil | Canon |
| Seiwell, Charles Mauck | 1st cousin 5 times removed | IX | 7 |
| Seiwell, Charles Valentine Koenig | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Charles W. | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Charlotte Claton | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Debora Westpher | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Edward A. | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Elick Devese Ruppert | Great-grandfather | III | 3 |
| Seiwell, Elizabeth Glass | 3rd great-grandaunt | VII | 6 |
| Seiwell, Elizabeth Jung | 5th great-grandaunt | IX | 8 |
| Seiwell, Emma Eliza Koenig | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Eudelia Kester | 2nd cousin 4 times removed | X | 7 |
| Seiwell, George Franklin Koenig | 2nd cousin 4 times removed | X | 7 |
| Seiwell, George Glass | 3rd great-grandfather | V | 5 |
| Seiwell, Harriet | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Henry Claton | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Henry Horlacher | 2nd great-granduncle | VI | 5 |
| Seiwell, Henry Kester | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Henry S. Pennebecker | 4th great-grandfather | VI | 6 |
| Seiwell, Honora Westpher | 2nd cousin 4 times removed | X | 7 |
| Seiwell, Jacob Pennypacker | 4th great-granduncle | VIII | 7 |
| Seiwell, James William Hug | Father | I | 1 |
| Husband of the 7th cousin | | |
| Husband of the 6th cousin twice removed | | |
| Husband of the 7th cousin once removed | | |
| Husband of the 7th cousin twice removed | | |
| Husband of the 8th cousin | | |
| Husband of the half 8th cousin once removed | | |
| Husband of the 8th cousin once removed | | |
| Husband of the 8th cousin twice removed | | |
| Husband of the 7th cousin 4 times removed | | |
| Husband of the half 8th cousin twice removed | | |
| Husband of the half 9th cousin | | |
| Husband of the 7th cousin 5 times removed | | |
| Husband of the 9th cousin once removed | | |
| Husband of the 8th cousin 3 times removed | | |
| Husband of the 9th cousin twice removed | | |
| Husband of the 7th cousin 6 times removed | | |
| Husband of the 8th cousin 4 times removed | | |
| Husband of the 8th cousin 5 times removed | | |
| Husband of the 9th cousin 3 times removed | | |
| Husband of the 9th cousin 4 times removed | | |
| Husband of the 10th cousin twice removed | | |
| Husband of the 9th cousin 5 times removed | | |
| Husband of the 11th cousin once removed | | |
| Husband of the 10th cousin 3 times removed | | |
| Husband of the 10th cousin 4 times removed | | |
| Husband of the 11th cousin twice removed | | |
| Husband of the 12th cousin once removed | | |
| Husband of the 11th cousin 3 times removed | | |
| Husband of the 17th cousin | | |