You mentioned Brosnan and I may be of some assistance. My cousins (one in Virginia, one in Florida) and I (I'm in California) are doing family research and the Brosnans are a part of the puzzle. The sister of our great grandmothers was Hanorah Shea who married James Brosnan. He is buried, I believe, in Virginia City, Nevada. She's buried either there or in Holy Cross cemetery south of San Francisco. They had one daughter, Julia, who died in 1938 --- she never married.
We've found more Brosnan info on a site but I would have to spend some time checking out my files to find it. It may be of some help to you --- we've found multiple family connections.