Thomas married Anna Hennings on 30 Jun 1821 in New Orleans, Orleans, LA. Anna was born in Amsterdam; died on 25 Aug 1844 in Milliken's Bend, Madison, LA. [Group Sheet] [Family Chart]

1. Mary Clementine Fitzwilliam was born on 23 Jul 1822 in New Orleans, Orleans, LA; died on 29 Jul 1891 in Bryan, Brazos, TX.
2. Amelia Euphrasie Fitzwilliam was born in 1824 in New Orleans, Orleans, LA; died on 3 Dec 1898 in New Orleans, Orleans, LA.

Thomas married Elizabeth Mary Watson on 13 Jun 1846. Elizabeth (daughter of Ringrose Drew Watson and Frances Mahon) was born on 5 Apr 1816 in Limerick Co, IRE; died on 4 May 1883 in St Louis, St Louis, MO; was buried on 5 May 1883 in Calvary Cemetery, St Louis, MO. [Group Sheet] [Family Chart]

1. Thomas L Fitzwilliam was born on 2 Sep 1847 in Milliken's Bend, Madison, LA; died on 31 Mar 1926 in St Louis, St Louis, MO.
2. Frances Anna Fitzwilliam was born on 31 Aug 1849 in Milliken's Bend, Madison, LA; died before 1870.
3. Elizabeth Mary “Lizzie” Fitzwilliam was born on 16 Sep 1851 in Milliken's Bend, Madison, LA; died on 16 Jul 1941 in St Louis, St Louis, MO; was buried on 18 Jul 1941 in Calvary Cemetery, St Louis, MO.
4. Antynette Isadora Fitzwilliam was born in Oct 1853 in Milliken's Bend, Madison, LA; died in Oct 1853 in Milliken's Bend, Madison, LA.

James married Mary Byrne. [Group Sheet] [Family Chart]