Hello, I just came across your post re: Francis Duffin & Rose Mary Walsh your 3x GGrandparent's!! I believe, My 2x GGrandfather Roger H Duffin b 1806-1880 is his brother!!

On my Ancestry.com tree, his siblings are.. James b 1800-1880 - Felix b 1808-1871 - Randall b 1812-1866 - Nancy Ann b 1815-1880 -
Francis Sr b 1817- d 14 SEP 1888 in Vienna, Maries, Missouri and married Rose Mary Walsh b abt 1817 in Knockanully, Glenravel, Antrim, Ireland and d 28 MAY 1882 in Maries County, Missouri, USA - Michael b 1825-1888 - Patrick b 1838-1871 - I would love to confirm this and find out if you know who their parents are... Looking forward to hearing from you!!