Hello, I think me great-grandmother is the Mary O'Malley you're talking about. I believe there were five sisters that came over from Connemara originally and one went back. Mary married Thomas Folan (which became Foley). They lived in Chicago and had four children - William, Francis, Mary, and Elizabeth "Agnes".
There were actually nine sisters in total - four stayed in Connemara (originally, at least). My aunt Irene is the granddaughter of one of those four. She keeps up the family's farm in Derryrush and knows quite a bit about the family. Let me know what kind of information you're looking for and I'll ask her.