Sidney Unwin was born 1873 in Hatcham, Kent, England, United Kingdom to Edward Unwin (1840-1933) and Elizabeth Spicer (1841-1921) and died 30 May 1962 Omakau, Otago, New Zealand of unspecified causes. He married Grace Ethelwyn Stalley (1880-1961) 28 November 1913 in Church Street, Timaru, Canterbury, New Zealand.
|Edward Unwin (1870-)|
|William Howard Unwin (1871-1945)||10 December 1871 Greenwich, Greater London, England, United Kingdom||25 December 1945 Timaru, Canterbury, New Zealand||Phyllis Agness Florence Hall (-)|
|Sidney Unwin (1873-1962)||1873 Hatcham, Kent, England, United Kingdom||30 May 1962 Omakau, Otago, New Zealand||Grace Ethelwyn Stalley (1880-1961)|
|Mabel Lizzie Unwin (1874-1933)|
|Basil Unwin (1876-1877)|
|Cyril Unwin (1878-1933)||1878 Lewisham, Greater London, England, United Kingdom||26 April 1933 Canterbury, New Zealand||Grace Eugenie Curline (-1970)|
|Ella Unwin (1880-)|
|Bernard Unwin (1881-1941)|
|Stanley Unwin (1884-1968)||19 December 1884 Handen Road, Lee, Greater London, England, United Kingdom||13 October 1968 England, United Kingdom||Alice Mary Storr (1883-1971)|
Sidney spent time in Orange River Colony, South Africa, before coming to New Zealand in about 1910.
|Helen Unwin (1916-)|
|Robert Sidney Unwin (1918-1996)|
|Eirene Ethelwyn Unwin (1919-1971)|