Hi Wendi,
Thanks for your interest.
Two of my wife's relatives died recently, husband and wife, and it seems they'd started a family tree. As we've now taken up the mantle, we've been looking through the details they'd collected and found a scrap of paper that mentions "O'Brien, Irish, Manchester Regiment, Ladysmith Barracks, 1920" .
It may prove to be nothing, but we just don't know.
Concerning his age, I honestly don't know.
Jangle