The lyrics in the DT database are flawed as discussed in an earlier thread here.

The name of the song is Pretty Peg or Peggy. It is a particular version of a song generally known as The Creel or "The Keatch on the Creel". IF you follow the links at the top of the thread there are discussions on other versions of the song.

Creggs or Craigs Pipes is the name of the reel that the Bothy band play after the song.

Leenia the song says that the singer rocked the mother in the basket. Maybe this is a euphamism for rape, but I have my doubts.