I'm a little confused - I thought your family was from John Costain + Ann Duke - the mother of Ann Duke was Ann Taubman

Re John Costain - there are at least 5 possible John costains born 1817-1819 - one I can provisionaly rule out is s/o richard & elizth cubbon as I can identify him in 1851, another probable non contender is s/o richard + jane harrison;
this leaves s/o john + margt bell bapt Arbory 18190926, s/o Ricard + Jane Duke Arb 18170310 & s/o John + jane corkish Arb 18170303

there may well be others