Lillian, Rigby is not one of the lines I am researching in Lawrence and Mercer Co. I was just suggesting some of the places I have had success searcing in this area. In doing so I took the two names the questioner was asking about and checked the New Castle Public Library Marriage and Obituary database to see how many entries were there. This database does not generally cover as far back as 1804 because it is for newspaper articles, but I have used it frequently to fill in maiden names and parents, children and siblings as found in obituaries. The only suggestion I might have for you would be those histories of the area that were written in the late 1890's and early 1900's. If you have a descendant who stayed in the area, there is often a brief history of an ancestor.
I am sorry not to be of more help to you. Good luck in your research.