Hi Lisa & Rosball,
Have checked all those avenues, with little success.
The only light I have achieved is a, [possibility], that a William Vincent & Maria Hayes had a child named Henry. Henry's name appears on some of his siblings Birth Certificates. William & Maria left Tassie to go and make their fortune on the 'Gold fields' in Ballarat & Castlemaine.
Supposedly, Henry died in Victoria circa 1860's. He was declared as dead in 1864, on his sister' [Emily],Birth Certificate. [No Death record either in Victoria or Tassie].
William was good at advising the Government, of his children being born, and those that had died.
On Maria's Death Certificate it has a 'Henry' being one of the witnesses to his Mother's death.
All living children were listed on that Certificate, in the far right of the column, there was no mention of Henry.
I have contacted the Castlemaine F.H.S. who hae spent a fair bit of time on this request, all to no avail.
I have drawn the theory that Henry does/did not want to be found.
Thanks everyone for your help.
George