I have been looking more at Jane Pavey. she is shown in 1861 census as born 1797 in Westdown, but 1841 census shows born circa 1805.
Where was she and family in 1851? Only one I can find who looks like it is Jane Pavey 40, ie born cira 1811, but born Westdown, and in same house hold as Mary Davis unmarried born circa 1836 and who is niece to head of household Elizabeth Mason, widow, born circa 1723 Tawstock.
Children John and Charles, although shown born Bideford, are probably in Green Lane Barnstaple in 1851 census, shown as lodgers but next door to elder sister Elizabeth and husband Richard Shaddick. But where are Mary (possibly dead?), Samuel and William