| Family Name | Source of Relationship |
|---|---|
| Cabe/McCabe | Related through a DNA connection to me. |
| Cadden | Related through descendant Orla Brogan's DNA connection to me and Marie "Michie" Michele McCabe-Velardi. |
| Caffet | Related through marriage to a DNA connection to me. |
| Callaghan/O'Callaghan | Related to me through at least two DNA connections. |
| Campbell | My 3x great grandmother, Mary Campbell, and four other Campbell families related to me. |
| Cannan | Related through my Geortler/Jecker Family Connections |
| Carberry | Related to me through two Carberry families. |
| Carew | Related through Carew relatives John Sorli and Marie Sorli, each with a DNA match to me. |
| Carey | Multiple Carey families related to me thru DNA connections to my 4th cousins, Sheila McCoy and Joan Rossillo. |
| Carmichael | Related through the family of my great aunt Catherine Kernan's daughter, Mary Connor/O'Connor. |
| Carragher | Related to me through several DNA connections. |
| Carroll | Related to me through several DNA connections. |
| Cassidy | There are currently three known Cassidy families that have connections to me. |
| Castaldo | Pasquale & Maria's great-grandson, Patrick Castaldo, has DNA matches to my neice, Megan, & my 4th cousins, Joan Rossillo & Sheila McCoy. |
| Chalmers | Scottish family related to me through my DNA connection to Angela Chalmers |
| Child | Related through James McCabe & Margaret Flynn of Dunleer area of Co. Louth, Ire. |
| Chiles | Related through my great, great uncle Henry McCabe of Dunleer area of Co. Louth. |
| Cleary | Related through my Morrissey Family |
| Clerkin | Related through my DNA cousins. |
| Clifford | Related through my Geortler/Cannan Family Connections. |
| Clinton | There are currently xxx known Clinton families that have connections to me. |
| Codair/Coderre | There are Codair/Coderre people, with McCormack ancestors, with those McCormacks being related to "my" McCabes thru DNA tests. |
| Cole | Related as Joseph and Elizabeth (nee Byrne) Cole's granddaughter, Susan Cole has a DNA match to me & my niece Megan McCabe. |
| Collins | Related through my 3x great grandparents, Nicholas and Betty Murphy of Co. Louth. |
| /Connell/O'Connell | Related to me through at least one DNA connection, maybe more. |
| Connolly | Connolly families with DNA connections to me. |
| Connor/O'Connor | Related through my Kernan Family |
| Cooney | Related to me through the James McCabe & Margaret Flynn of Dunleer area of Co. Louth, Ireland family. |
| Corrigan/Kerrigan | Corrigan/Kerrigan family with a DNA connection to me. |
| Cosgrove | There are currently three known Cosgrove families with connections to me. |
| Cotter | Related as Anna G. (nee McCormack) Cotter descends from "my" Kennedy/McKenna Co. Louth, Ireland family. |
| Coyle | There are currently two known Coyle families that have connections to me. |
| Crean | James A. and Hannah (nee Reagan) Crean's great-granddaughter, Catherine Walsh has, according to Family Tree DNA.com, an autosomal DNA match to me. |
| Crilly | Related through Henry McCabe of Dunleer area of Co. Louth. |
| Crolly | Perhaps related through my McCabes of the Dunleer area of Co. Louth. |
| Crudden | Related through my DNA cousin Éamonn Mac Rodáin's extended family. |
| Crumb | Related through my 3x great grandparents, Nicholas and Betty Murphy of Co. Louth. |
| Cullen | Cullen families related to me through autosomal DNA testing. |
| Cummiskey | Cummiskey descendants with a DNA match to me, and matches to Joan Rossillo, and to Michie McCabe-Velardi and her uncle Peter. |
| Cunningham | Multiple Cunninhgham families related to me. |
| Currier | Related through my DNA cousin Sadie Cosgrove's family. |
| Custer | Related through my great aunt Catherine C. (nee McCabe) Mahoney, of James and Catherine (nee Morrissey) McCabe. |
