Hi again,
I am doing some guessing here. Are you saying that Richard Cox married another woman called Harriet before 1838?
I found the 16 year old Richard's baptism on the IGI and he seems to be a Richard and Harriet's son, along with a William 1837 and a Sophia 1831. Another IGI ref and a FreeBMD marriage gives Harriet's maiden name as Greenaway married 1838 in the Abingdon Reg Dist. Dec Quarter
Abingdon Dec 1838 6 246 Cox Richard /Greenaway Harriet
Are you saying that you have proof that this is the same Richard Cox, and he was a widow in 1838 so there was an earlier marriage? If so, looking for a death/burial of the first Harriett might be productive, at least in establishing her age.
Vicwinann