I was able to get a copy of that same photo from Cornelius' daughter. The obit for Patrick T. Brosnan lists his wife as Joan Griffin (Johanna). His 4 sons John P., James T., William F. (my grandfather), and Austin J. The obit may also have only listed his surviving siblings of John, Thomas, William, and Cornelius and Mrs. Patrick (Bridget) O'Dowd of Ireland.
The obit lists his parents as Thomas P Brosnan and Elizabeth Sullivan (not O' Sullivan). any further info would be appeciated.