I have a John Crisham who married a BRIDGET WALSH. I estimate their births to be around 1830. They had a son John b. 1866. I know the Crisham family lived in a town called Tygreenaun, Barnaderg in Galway but I have no info on Bridget's family. I don't know if this is of any help but I thought I'd pass the information along to you.
Good luck. Let me know if you come across a Bridget in your tree.