(ABT 1780-)
| +---James Trethewy
| +---James Trethewy (ABT 1681-)
| +---James Trethewy (ABT 1716-)
| | | +---Theophilus Coad
| | +---Grace Coad 
+---Grace Trethewy (ABT 1750-25 FEB 1823)
+---Gertrude Pye (-JUL 1772)