Hi! My grandma was a Donegan. In some of her papers, John's parents are listed as "Patrick John Donegan" b.1782 Ireland and Mary Vorhees b.1785 New Jersey d.7 Apr 1870 in Glen Rock, Bergen, NJ.
I've been searching for more information about them, especially about Patrick. It's not easy without at least a birth city or exact date. There's a few Patrick's in Ireland...lol. Hope this helps! Check out my family tree for more Donegan info/papers.