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I’m having trouble identifying my 3 x GGF John Birch. He was (according to birth certificate and marriage certificate of my 2 x GGM his daughter) born in Armagh approximately 1809. I haven’t found how he travelled to Australia, where he landed or where/when he died. It is noted on my 2 x GGM birth certificate that John Birch married Susan Doherty in van diemans land in May 1851 but I cannot find this record. It is possible  they didn’t officially marry as she WAS married in 1848 in VDL to another man Walter Neiles, had a son with him also called Walter, who died in 1850 aged 2. She had another child by Walter who survived , a daughter called Sarah Jane Neiles. I cannot find any birth entry for Sarah either, only marriage record later in Victoria.
Walter seems to be out of the picture after this, as Susan and John Birch turn up as parents in 1853 with birth of son Joseph Henry Birch in Victoria, and then in 1856 my 2 x GGM Emma Jane is born in Kyneton, Victoria.
After that Susan Birch pops up a lot in newspaper articles on the Victorian goldfields, she seems to have been quite the character, but the only mention of her husband is in 1881 in an article where she claims he died 18 years earlier (about 1863) at pleasant creek ( now Stawell) , but again cannot find this record.
I have searched convicts coming to VDL and NSW- there were 12 John Birch’s who were transported to Australia - none of them match my John’s DOB or come from Ireland. It’s possible he was born in Armagh but lived in England and traveled from there but I can’t define MY John Birch. Please if anyone knows or can help me, this ancestry is an anomaly.