+---William Robert Tretheway (ABT 1832-1918)
+---Harry Tretheway (ABT 1879-18 APR 1926)
| | +---John Davey
| +---Emma Davey 
(ABT 1844-)
| +---Amelia Payne (ABT 1810-)
William Robert Tretheway (06 SEP 1919-1994)
+---Ethel Frances Searle (1881-21 JAN 1961)