McCullough and Maffet Families - Rathfriland

Good day to all,

First, I must give my compliments as I find this a beautifully made website!  I have posted this message as well for the parish of Drumballyrooney as I understand that Rathfriland straddles both parishes and I hope, that in doing so, that I am not comitting a faux-pas.

I am looking to find any information regarding these families (McCullough and Maffet) both, apparently, from County Down in or near Drumballyrooney, Drumgath - Rathfriland.

My ancestor was Elizabeth McCullough who emigrated to Philadelphia, Pennsylvania in 1765 or thereabouts.

She left with her husband Robert or David  (there are conflicting accounts of his given name) Maffet, along with her mother (name unknown) and two brothers, James and David.  A third brother, William, apparently stayed behind and later emigrated to England.  The Maffet family may have been from Drumdreenagh Townland.

David McCullough was apparently born/christened in Rathfriland on April 7, 1738, was a sea captain, and traded to Ireland, in bringing over passengers, on his last trip, he and his brother James were wrecked on the coast of Wales (date unknown), lost their ship (name unknown), but survived.  I believe this family must have had extensive trade and maritime connections both before and after the emmigration to America as many of the men followed maritime professions and were succesful mariners, masters of their own vessels and often privateers in times of war

This is the same family which was featured in an episode of the American genealogy show "Finding your Roots" in May 2012 and which featured the lineage of the famous Jazz artist and movie actor Harry Connick Jr. (as he is a descendant of David McCullough).

http://www.dailymotion.com/video/x1c9jqd_finding-your-roots-s01e01-branford-marsalis-and-harry-connick-jr_tv
The segment dealing with David McCullough begins at 44 minutes 27 seconds...

Any help would be greatly appreciated in helping us trace our lineage in Ireland (and, with any luck, further back into Scotland).