Hi
Yes I know on line tree should be treated with caution but as this one did have photos I thought Sandiehawk could have a look and see if any of them looked familiar or struck a bell.
Obviously all information should be checked against original records.
As for the baptism I've only looked at the transcript ,not the original ,its possible the transcriber turned Cobden into Cockburn ,I don't know but thought it worth a mention.
The tree I noticed was this one.
http://trees.ancestrylibrary.com/tree/21978863/person/1188460712?ssrc=&ml_rpos=1owned by caesiajcm.
I couldn't find a Thomas Robertson marrying a Harriet White as per the Australia death index but it seemed reasonable with this Alexander's mother being a Miss White and dying when he was about 5 that who ever filled in his death certificate might have mixed her up with the stepmother they remembered called Harriet.
I've checked the marriage and there was a Thomas Robertson marrying a Harriet Jones in Victoria in 1855 registration number 82.
I can see a death registration that would match the tree Mount Blackwood Victoria 1888 Thomas Robertson age 88 father John .
Hart (Harriet) Robertson age 67 Myrniong Victoria 1891 daughter of Thomas and Grace Jones seems to be the stepmother.
Obviously it needs a bit of digging and Alexander's death certificate would perhaps add new details to follow up.
However looking at the map Ballan Cemetery and Mount Blackwood ,Myrniong all seem very local.
Some of Thomas and Harriet's children died at Ballan.
James 1859-1927
David 1861-1935
William Henry 1858-1946 at Ballarat like Alexander in 1931
Cath Horsely 1861-1942 Footscray Victoria their married daughter is a bit further away.She and David were twins born 25 Dec 1861 bapt at St Peters Eastern Hills Melbourne .Father a farmer from Pentland Hills.
Their other child Harriet Ann 1856-1857 just says Victoria.
Have a look and see what you think.
Ciderdrinker
