Here is the comical version I promised:

THREE SISTERS
Adapted by Fiddlesticks (Rebecca, Kathryn, and Elizabeth Davis)

There were three sisters side by side,
Sing I dum, sing I day,
There were three sisters side by side,
The boys are bound for me,
There were three sisters side by side,
The eldest for young Johnny cried,
I'll be true unto my love, if he'll be true to me.

Johnny bought the youngest a gay gold ring
He never bought the eldest a single thing

Johnny bought the middle one a fine green hat
The eldest didn't think much of that

As Johnny went a-walking by the foamy brim
The eldest pushed poor Johnny in

And so beware you suitors all
Or in the foamy brim you'll fall.

I suppose the biggest part of the humor is the disdainful note in the eldest sister's voice as she sings the last line (not including burden) of each verse.