| Name | Relationship with Susan Foster | Civil | Canon |
| Highsmith, James Allen | Half 2nd cousin 3 times removed | IX | 6 |
| Highsmith, James Newton | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, James R. | 1st cousin 3 times removed | VII | 5 |
| Highsmith, James W. | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, James W. | 1st cousin 3 times removed | VII | 5 |
| 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Jasper N. | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Jessie Lee | Half 2nd cousin 3 times removed | IX | 6 |
| Highsmith, John | 5th great-grandfather | VII | 7 |
| Highsmith, John | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, John A. | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, John M. | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, John Thomas | 3rd great-granduncle | VII | 6 |
| Highsmith, John Thomas | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Joseph Henry | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Judith | 4th great-grandaunt | VIII | 7 |
| Highsmith, Keziah E. | 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Lanie | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Leighton | 1st cousin 3 times removed | VII | 5 |
| Highsmith, Leonard D. | Granduncle | IV | 3 |
| Highsmith, Lucretia | Half 3rd great-grandaunt | VII | 6 |
| Highsmith, Lucretia | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Lydia | Half 3rd great-grandaunt | VII | 6 |
| Highsmith, Martha Elizabeth | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Martha L. | 1st cousin 3 times removed | VII | 5 |
| Highsmith, Mary | 4th great-grandaunt | VIII | 7 |
| Highsmith, Mary | Half 3rd great-grandaunt | VII | 6 |
| Highsmith, Mary | Half 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Mary E. | 1st cousin 4 times removed | VIII | 6 |
| Wife of the 2nd great-granduncle | | |
| Highsmith, Mary L. | 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Mary M. | 1st cousin 3 times removed | VII | 5 |
| Highsmith, Matilda W. | 1st cousin 3 times removed | VII | 5 |
| Highsmith, Mattie | Grandmother | II | 2 |
| Highsmith, Mildred Harriet | Half 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Millie E. | 1st cousin 3 times removed | VII | 5 |
| Wife of the half 1st cousin 4 times removed | | |
| Highsmith, Minnie Lee | Half 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Moses | 2nd great-granduncle | VI | 5 |
| Highsmith, Nancy | 4th great-grandaunt | VIII | 7 |
| Highsmith, Nancy | Half 3rd great-grandaunt | VII | 6 |
| Highsmith, Noah | 2nd great-grandfather | IV | 4 |
| Highsmith, Noah | 1st cousin 3 times removed | VII | 5 |
| Highsmith, Nole | Grandaunt | IV | 3 |
| Highsmith, Owen K. | 2nd great-granduncle | VI | 5 |
| Highsmith, Patsy | Half 3rd great-grandaunt | VII | 6 |
| Highsmith, Perry | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Robert B. | Half 2nd cousin 3 times removed | IX | 6 |
| Highsmith, Roxie | 1st cousin 4 times removed | VIII | 6 |
| Highsmith, Samuel | 1st cousin 4 times removed | VIII | 6 |