As you feel that the Burton family in 1841 is the Newton family, how about getting Lucys birth certifcate as she was born after registration to see what is says about her mother....... a word of warning though, even if it says "formerly" whatever it still does not signify that a legal marriage took place.
Other than that I dont know what to suggest .
Having said that I cant seem to find Lucy,s birth registration are you sure that she is 1 month on that census if it very feint
as I cant seem to pick that up on Ancestry
