I used to sing "The Two Sisters", mainly from Clannad's version, with a verse or two from Sharp's Appalachian text which seemed to fill out the story. I sang it once when Andy Irvine was the guest at the Lane Ends Folk Club, Wesham, near Blackpool. He came over afterwards to say that he had set the tune to those words, but that Clannad and others who recorded the song had either not known or had somehow failed to mention that. He had always felt slightly miffed about the missing attribution, but somehow never got round to recording the song in that version.
He seems to have continued his fascination with the tune, using it for "They'll Never Believe It's True" on his "Way Out Yonder" album. Explanation from the Andy Irvine Lyrics fan website -
"THEY'LL NEVER BELIEVE IT'S TRUE
(Andy Irvine, Steve Cooney) (Andy Irvine)
This was meant to be a song called "The Two Sisters" that I found in a Cecil Sharpe collection many years ago. I'd always been a bit irked that some people, who recorded it subsequently, had seemingly not known that the tune–and some of the words–were mine. The bit about ''Boiled in Lead'' for instance. However when we put the backing track down, Steve was entranced by it and decided it was "Faerie Music". We banded around ideas for a week or two and one morning, when I woke up, this song greeted me ! Needless to say not ALL of it is true…"
They'll Never Believe It's True/froggy's Jig