Hi My great grandmother was Johanna Brosnan born 3 July 1852 in Castleisland. She left Ireland with her parents Mary Kerin and Thomas Brosnan and four sisters for New Zealand in 1874 where she married Timothy Twomey also of Castleisland. Timothy was from the forge in Castleisland.
I see you are talking about a Kerin marrying a Brosnan in Castleisland. Different people but must be same families.
Can you share any information. thanks