Many thanks for all your helpful replies !
I dont know who his parents were, but have looked at Christopher and wife Ann Johnston who arrived in 1854 and he was under 1yr.
I wonder if Thomas and William would therefore would have been his brothers.
I wonder where the great niece came to be living with him [Mary].
Was he married in Aus after 1903 and did he have a further family or child???
I can not trace his children in NZ [Margaret b1888 and William b1891 ]. Christopher jnr his eldest son i have all relavant info. Thanks Jeanette