Sorry it took me so long to reply. I'm thrilled to hear from another Duffy descendent.
I'm the great granddaughter of John Duffy, one of the 12 brothers. My maternal grandmother was Ellen Duffy, daughter of John Duffy and his wife Margaret McLaughlin.
Which child of Michael and Johanna are you descended from? Do you have a copy of the picture of the 12 brothers and their sister Bridget.
My family has been having lots of fun researching this amazing family.