They were George Foster b 1844 Astbury/Congleton, Cheshire and Mary Ann Rowland b 1848 Cape of Good Hope, South Africa (one census has her as being born in Cap Hop, Sussex) Every one of Mary Ann Rowlands antecedants were military - all 73rd Foot.
1891 they were in Queen Elizabeth Terrace, Epping, Chingford, Essex - William is 10 and a scholar.
I think 2 of his younger siblings die here - certainly a daughter dies age 7.
1901 43 Baker Street, Islington/Finsbury - Parents and other children on census but no William - he is away at the Boer War.
1911 - had been living at 14 Woodstock Road, Stroud Green, Hornsey BUT disappeared (William was married and living elsewhere as where many of the other children). It is thought Mary Ann died in 1903/4 and George died January 1911 of emphysema and chronic bronchitis. It is possible they are buried in Highgate Cemetery but not confirmed.
William himself was buried in a CWG in the churchyard of Alderbury St. Mary, Wiltshire in 1942 - he was living here after he retired from work in London (he worked for the London NE Railway I think and these records are now on ancestry). He may have worked for the NAAFI in Wiltshire after his retirement from London but this is not confirmed.
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Sue