If Protestant, then its likely that your Lahey / Lahy / Leahy branch descended from County Cavan, Ireland [Probably of Huguenot descent].
I've written a book on the Origins of this County Cavan family - available on Amazon - "The Cavan Leahys: Origins". 2nd Volume to follow in 2018. I also created a FaceBook Group "Cavan Leahys"
Feel free to email me at cavanleahys@gmail.com if you have stories / photos etc. of this family or want to know where your branch fits in
Regards
David Leahy