Traci - I don't think I can help you, because I'm in the same boat your are. My grandma's mother was Hannah Sullivan (Born 1866 in Ireland) and she married John McCarthy. They lived in Ironwood and had 4 kids there before they moved to Butte, Montana. Hannah came to the US in 1884. I can't find anything about what ship, port of entry or even if she was accompanied by family.
Hannah's mother-in-law was Kate O'Sullivan wife of Jerry McCarthy. Kate O'Sullivan McCarthy was born in Ireland in 1853. I know nothing of her family or arrival in the US.
I am grasping at straws...do any of these names and/or dates match up with anything you have? Thanks so much if you can help.