"Mary had a little lamb" had long been a popular choice for blues musicians to jam and solo on stage. Ever since watching the rendition by Buddy Guy and Stevie Ray Vaughan, it also had been one of my favorites to solo blues on.
Just recently I though about this: it makes sense to me that songs with context and lyrics like "Crossroad", "Johnny B. Good", "Sky is crying", "Sweet home Chicago" etc. are blues.
But I do not get why "Mary had a little lamb", supposedly a 19th century nursery rhyme, was taken and rendered by blues musicians. Does anyone know the history or background of how this transformation is made?
I would assume there is a story behind or else many of its likes such as "London bridge is falling down" or "Twinkle twinkle little star" would also be re-rendered as blues songs (but they don't, at least to my knowledge), and these are certainly more well-known than "Mary had a little lamb".