Nicholas,
Was the Pat in your family married to a Hanora Blackwell? If so, I might have found a link. The Patrick in my family was married to Hanora Blackwell on May 14,1854. Had my 2nd gr grandfather Frances H. Galvin on January 19, 1859. In the 1880 census Frances was living with F.H. Blackwell his uncle. I don't know ,if there were any more siblings. On his marriage registration his father was a John Galvin.