Are you sure that Patrick McGuire jr. never married? If it is my gGrandfather (and I'm not 100% certain because I just started), he married a MaryAnn Gallagher, and they only had one living offspring, my grandmother Catherine (McGuire) "Kitty" Haggerty. She married Robert Haggerty and had five children. They moved to Detroit around the start of WWII.
Maybe it isn't, but I've been reading through your posts, and it seems that it has to be him. I've just started researching, so i have no documentaion, but my Patrick McGuire adopted one of his nieces (believed to be one of his brother's daughters.) Her name is Margaret (Peggy). She still lives in Scranton. I am going top contact her asap and see if you and I are related:)