I may have some information that may relate to your genealogical research. My gg grand-aunt Bridget Farrell married James Barry at St. Patrick's Parish in Montreal on Oct. 10, 1865. His parents were William Barry and Mary Laird. As I researched further into the Catholic records, I found out that the sponsor for Bridget and James' first child, Mary Barry on Aug. 2, 1866, was Michael Barry. Although I did not confirm if the record informed Michael was a brother, I feel confident that he most likely was.
Also, based on James' parents, I was able to determine he had 4 other sibblings that married. They were:
Ellen Barry married Patrick Sullivan 7-Jan-1874 St. Ann's Parish Jane Marie Barry married Patrick Meeney 15-Jun-1866 St. Patrick's Parish Elizabeth Barry married William McNulty 10-Feb-1879 St. Ann's Parish William Barry married Bridget Ryan 17-Jun 1862
If this information matches your findings, I have more information on the decendants of Bridget and James.