Hi Old Rowley
Thanks a million for your suggestions - it's great to have everybody's input and I didn't have any idea where to go next.
My mum and all her family are no longer with us and the few cousins remaining are too young to remember any discussion about John. My brothers and sisters all remember my mum's stories, so I am anxious to close one of the most interesting loose ends in the family history.
You do get hooked on it all - and as you close off one dead end, another beckons !!
Once again, thanks for your help and I'll keep you posted on my progress or lack of it.
Cheers
Anna