Sorry Bruce, I was assuming it was Scottish because of the use of the word "twa" for "two" in the version called Twa Sisters. It also uses other Scottish words like "sae" & "bonnie" etc.
THE TWA SISTERS
I says to my dear sister, "Are ye comin' for to walk?"
"Ayee O, an' sae bonnie, O"
"An it's I'll show you wonders before we go back."
And the Swan it swims sae bonnie, O.