| # | Children | Name | Born | Died | Father | Mother |
|---|
| 1 | Yes | | b. 25 Oct 1874 | d. 12 Dec 1919 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 2 | Yes | | b. 6 Jun 1877 | d. 6 Jul 1951 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 3 | Yes | | b. 27 Jan 1880 | d. 10 Jul 1957 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 4 | | | b. 17 Jul 1882 | d. 25 May 1960 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 5 | | | b. 8 Jan 1885 | d. 27 Feb 1918 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 6 | | | b. 16 Nov 1886 | d. 31 May 1912 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
| 7 | | | b. 24 May 1889 | d. May 1950 | Dr John James O'Brien | Elizabeth Mary “Lizzie” Fitzwilliam |
1846 - 1889 (42 years)