Here are two Appalachian versions, one sung by Dr. Patrick Gainer, West Virginia's great ballad collector, and the other sung by Maggie Hammons, from a well-known family of "source singers".

Both these versions have the oldest sister pushing the youngest into the water and then rejecting her pleas for help as she drowns. The first includes the tell-tale fiddle but no miller. The second includes the miller but not the fiddle.

http://www.libraries.wvu.edu/wvconline/patrickgainer.htm

Kent