Jane Pavey (nee Davis) can be found on the 1841 census for the parish of Barnstaple, with her are three of her children Elizabeth b. 31st May 1824, Mary b. 8th July 1829 & John c1840 all baptised in the parish of St. Peter's Barnstaple.
John does not appear on the census record and I have no clues as to where he was born.
Steve