Hi Chris
Very grateful for any help - I have found John Dudley on the 1841 Census in Audlem, Nantwich, Cheshire (parish of Dodcott Cum Wilkesley), b c1779.  His son Thomas and daughter Elizabeth are with him.  John is a widower.  His son, John, moved to London, married and brought up his family there - he was born c1813 so I am looking for his father John's marriage probably pre1813 but I don't know if there were any other children born earlier.
Many thanks
Pearly22