I just tried to email you, but the message was returned.I have also traced my Donegan roots to County Louth. My grandfather, Thomas Donegan, was born in 1860.(According to the US Census of 1900.) In 1882 or 1883 he married Mary McCue of Milestown.In 1884 they had a son, Thomas.In 1885 (according to the 1920 Census) or 1886 (according to the 1900 Census) they emigrated to NY.
I have been able to find Mary McCue's family in the Parish of Kilsaran, C. Louth records, but not Thomas Donegan.After reading your postings, I'm wondering if my grandfather could be part of the Drogheda line.