I'm looking for information on my Grandfather John Roberts

This all I know to date:

born ?? England

Emigrated To NZ ??

Unsure If John And Ethel Married ??

was living in Taylor Street Carterton New Zealand
John Roberts Was Also Know As Jack When He Lived In Carterton NZ.

Ethel Emma Spackman Was Living With Him In Taylor Street carterton At The Time They Had Children As Follows:

Doris Ethel Roberts Born 1911
Albert john Roberts Born 1912
NR Roberts Born 1914 (Still Born)

Twins
Henry Edwards Roberts Born 1918 Oldest
Ernest Roberts Born 1918 Youngest