William married Catherine Scolier on 30 Dec 1785 in St. Blazey, Cornwall, UK. Catherine (daughter of Richard Scolier and Mary Hill) was born before 1 Mar 1765 in St. Blazey, Cornwall, UK; died before 10 May 1815 in St. Ewe, Cornwall, UK; was buried on 10 May 1815 in St. Blazey, Cornwall, UK. [Group Sheet] [Family Chart]

1. Mary Trethewey was born before 10 Sep 1786 in Luxulyan, Cornwall, UK.
2. William Trethewey was born before 22 Jun 1788 in Luxulyan, Cornwall, UK.
3. Jennepher Trethewey was born before 10 Mar 1793 in St. Blazey, Cornwall, UK.
4. Grace Warne Trethewey was born before 3 Jul 1796 in St. Blazey, Cornwall, UK.
5. Richard Trethewey was born before 10 Mar 1799 in St. Blazey, Cornwall, UK.
6. John Trethewey was born before 9 Feb 1806 in St. Blazey, Cornwall, UK.