No one has mentioned the charming children's book about this tune, so I will! On Christmas Day in the Morning: A Traditional Carol. John Langstaff (who included the song in his Christmas Revels) wrote the forward to the book which includes some history, and Melissa Sweet was the illustrator credited with authorship for this 1999 publication. My husband and I have used "There Was a Pig Went Out to Dig" for years in our holiday programs as a fun example of how animals were celebrated in more agrarian societies. Good for increasing vocabulary because the song as written here mentions a lot of farming terms unfamiliar to those living in an urban setting. The verses have a nice rhyming pattern that leads children and adults in a guessing game about the outcome: pig-dig, cow-plow, crow-sow, minnow-winnow, etc. Audiences may join in with appropriate animal noises. So much to love about this rollicking participatory tune! Here is a link to the book on Amazon: https://www.amazon.com/Christmas-Day-Morning-Traditional-Carol/dp/0763610550 but seek it in public library collections, too.