Have you seen this couple living in Tavistock in 1841:
Samuel Cox, 68, Foundry[?] Man, b Devon
Elzabeth [sic] Cox, 63, b Devon
Betsy Cox, 5, b Devon
http://search.ancestry.co.uk/Browse/...tock.ALL.10.11
HO107; Piece 249; Book: 13; Civil Parish: Tavistock; County: Devon; Enumeration District: 10; Folio: 13; Page: 21; Line: 10