(ABT 1809-)
+---Benjamin Thomas Birt (ABT 1835-25 JUN 1905)
| +---Catherine Simmons 
(ABT 1813-)
+---Benjamin Thomas Birt (ABT 1880-BEF 08 DEC 1960)
| | +---John Baker
| +---Jane Emma Baker
| +---Jane Armstrong
+---Victor Alexander Birt (24 DEC 1907-BEF 17 NOV 1978)
| | +---Alexander Peter Campbell
| +---Christina (Teenie) Margaret Campbell (ABT 1885-BEF 19 JUN 1986)
| +---Jane McKay
Derek Victor Birt (ABT 1932-)
+---Jean Eleanor Presswood