| Child 1 | Male James Grennan |
| Born | ||
| Christened | 14 Dec 1856 | Ballinahown Parish, Co. Westmeath and Offaly, IE |
| Died | ||
| Buried |
| Child 2 | Female Bridget Grennan |
| Born | ||
| Christened | 5 May 1863 | Ballinahown Parish, Co. Westmeath and Offaly, IE |
| Died | ||
| Buried |
| Child 3 | Female Mary Grennan |
| Born | 10 Jun 1867 | Moorock, Lemanaghan Parish, Co. Offaly, IE |
| Christened | 16 Jun 1867 | Ballinahown Parish, Co. Westmeath and Offaly, IE |
| Died | ||
| Buried |
| Child 4 | Male + Michael Joseph Grennan |
| Born | Apr 1870 | Co. Offaly, IE |
| Died | 13 Sep 1926 | Bristol, CT, US |
| Buried | ||
| Spouse | Mary Ellen Galvin | F890 | |
| Married | 25 Jan 1893 | Bryn Mawr Chapel, Bryn Mawr, PA, US |