| Name | Relationship with Natalie Seiwell | Civil | Canon |
| Sinclair, William Of Rosslyn | 21st great-grandfather | XXIII | 23 |
| 2nd cousin 21 times removed | XXVII | 24 |
| 3rd cousin 20 times removed | XXVIII | 24 |
| 3rd cousin 22 times removed | XXX | 26 |
| 3rd cousin 23 times removed | XXXI | 27 |
| 5th cousin 19 times removed | XXXI | 25 |
| 3rd cousin 24 times removed | XXXII | 28 |
| 5th cousin 23 times removed | XXXV | 29 |
| 5th cousin 24 times removed | XXXVI | 30 |
| 5th cousin 25 times removed | XXXVII | 31 |
| 8th cousin 19 times removed | XXXVII | 28 |
| 8th cousin 20 times removed | XXXVIII | 29 |
| 8th cousin 21 times removed | XXXIX | 30 |
| 8th cousin 22 times removed | XL | 31 |
| 8th cousin 23 times removed | XLI | 32 |
| 8th cousin 24 times removed | XLII | 33 |
| 8th cousin 25 times removed | XLIII | 34 |
| Sinton, Isabella | 20th great-grandmother | XXII | 22 |
| 21st great-grandmother | XXIII | 23 |
| Wife of the 21st great-grandfather | | |
| Wife of the 2nd cousin 24 times removed | | |
| Wife of the 2nd cousin 26 times removed | | |
| Siwardsson, Osbeorne | 28th great-granduncle | XXXII | 31 |
| Siwardsson, Toste | 28th great-granduncle | XXXII | 31 |
| Siwardsson, Waltheof II | 28th great-grandfather | XXX | 30 |
| Smith, Barbara Jean Siegfried | 7th cousin once removed | XVII | 9 |
| Smith, Edward | 3rd great-grandfather | V | 5 |
| Smith, Florence Alda Bucher | Wife of the 6th cousin twice removed | | |
| Smith, Harold Bunnell | Husband of the 6th cousin twice removed | | |
| Smith, Janet Elise Siegfried | 7th cousin once removed | XVII | 9 |
| Smith, Marilynn Louise Siegfried | 7th cousin once removed | XVII | 9 |
| Smith, Mary Ellen Shipley | 2nd great-grandmother | IV | 4 |
| Sonreter, Maria | 10th great-grandmother | XII | 12 |
| Sophia | 7th great-grandmother | IX | 9 |
| Spencer, Margaret | 9th great-grandmother | XI | 11 |
| Sprakling, Sigrid | 32nd great-grandmother | XXXIV | 34 |
| Stacey, Joe | Husband of the 5th cousin 3 times removed | | |
| Stacy, Nancy | 5th great-grandmother | VII | 7 |
| Wife of the 1st cousin 6 times removed | | |
| Stapleton, Allan | 32nd great-grandfather | XXXIV | 34 |
| Stapleton, Avica Fitzalan | 25th great-grandaunt | XXIX | 28 |
| 4th cousin 29 times removed | XXXIX | 34 |
| 6th cousin 25 times removed | XXXIX | 32 |
| Stapleton, Brian | 22nd great-granduncle | XXVI | 25 |
| 7th cousin 26 times removed | XLII | 34 |
| 9th cousin 22 times removed | XLII | 32 |
| Stapleton, Brian | 31st great-grandfather | XXXIII | 33 |
| Husband of the 29th great-grandaunt | | |
| Stapleton, Brian Fitzalan | 25th great-granduncle | XXIX | 28 |
| 4th cousin 29 times removed | XXXIX | 34 |