Bill,
Well try as I might I cannot see any obvious link at this time-I thought Frances' observation (2005) interesting but as of yet-nothing... Are you able to check out the 1841 census that she refers to? here there is a Thomas and Ann living closely to a Thomas and Catherine (my ggrandparents) Did your ancestors go to Liverpool? You may have mentioned it previously but I can't recall, if they did do you know where they lived? All the Cubbin clan I knew when growng up were part of my father's family but my father did once mention a cousin of his fathers living there-though there were probably lots of them if the truth be know :-)
Ann