First at to above post how did I forget to add John Moulden to the list of good Irish Scholars. I knew someone was missing, but couldn't remember who at the time. An I might add Lani Herrmann also, and Michael O'Sullivan (That's not the way he gives it, but I can't spell it in Gaelic).
His intitials are at the bottom of the ballad sheet as author, and no prior versions seem to be know for the Child ballads. Two others which have become folksongs seem to be expansions of popular songs ("Now the tyrant has stole my dearest away" and the one the Copper family calls "The Haymakers", originally "The Countrey People's Felicity").
Thomas Robbins' 4 Child ballads (3 are about Robin Hood) are all revisions of earlier songs.