The Farmer in the Dell

Can someone please tell me why? Why is it that in the song, “the Farmer in the Dell,” the nurse takes the dog? Depending on which version you listen to, the nurse may even “take the cow.” I don’t know which is worse. Why can’t the nurse take the invalid or the defibrillator? I went to school for far too long to stand for this. From now on when you sing “the Farmer in the Dell,” please change it to, “the nurse takes the pills.” This version is much more realistic, especially for me.