I am descended from Marcus Daffy and Mary Darcy and their son Michael Daffy who married Bridget Griffin. My great-grandmother was Bridget Daffy who married John Killeen. My grandfather was Jeremiah Killeen.
I have some information on the Michael Daffy and Bridget Griffin family. They had twelve known children: 1) Marcus (1864-?)married Ellen Looney, emigrated (no details), "died young"; 2)Mary Daffy (1865-before 1911) married John Malone in the Parish of Kilmurry-Ibrickane; 3) Bridget Daffy (1867-1903) married John Killeen in the Parish of Kilmurry-Ibrickane; 4) Susan Daffy (1868-1935) married John Sexton in the Parish of Kilmurry-Ibrickane; 5)Peter Daffy (1870-1946) married Sarah King in the the Parish of Kilmurry-Ibrickane; 6) Ellen Daffy (1872-1943) married Patrick Murrihy in the Parish of Kilmurry-Ibrickane; 7) Margaret Daffy (1874-1892); 8) Anne Daffy (1876-abt 1949, Ireland), possibly a shopkeeper; 9) Honora Daffy (1877-1878); 10) Nora Daffy (1879-1977) married John Barry in the Parish of Kilmurry-Ibrickane; 11) Catherine Daffy (1880-?) No Information about her; 12) Michael Daffy 1886-1900).
I have information about the family of John Killeen and Bridget Daffy. Sons Michael and Jeremiah and daughters Eileen, Susan, and Delia emigrated to the United States. Michael and Jeremiah settled in Michigan. Eileen married Patrick Joseph Murphy in Michigan, but settled in California. Susan and Delia lived in Michigan, but returned to Ireland.
At ths point, I do not know anything about the ancestry of Marcus Daffy and Mary Darcy.