Here's some info from Jean Ritchie:

Most recently, "Love Somebody, Yes I Do!" is recorded on my, "Mountain Born" CD. The version I do is the one my family always knew- with some added lyrics by myself. I wrote the second half of the high-part or chorus, "Dance all night & fiddle all day (3 times)
                      & that's the soldiers' joy they say".
Also added the last verse "Love somebody fond and true (3 times)
                           Love somebody and I guess it's you!"

This is why I have the copyright,- just on my own version. I always tell about the absence of instruments in our part of the mountains in the early days of our family, and that folks remembered the tune played on fiddles and pipes, with the fast tempo and all the curilques but that the voice alone couldn't do all that, so they put words to it, and the tune got slowed down and "ironed out" to accomodate the singing voice. It's very effective when you follow the song with the fast fiddle version- a wonderful comparison!