John Duffy was born 1 July 1870 in Dublin, Leinster, Ireland and died 1 June 1930 Saint John, New Brunswick, Canada of unspecified causes.
Children
| Name | Birth | Death | Joined with |
| Sarah Agnes Duffy (1894-1959) | 1 June 1894 Saint John, New Brunswick, Canada | 19 July 1959 Boston, Massachusetts, United States | Walter John Donnelly (1888-1941) |
Siblings