I think (unless I have it wrong) that Jack may be bringing up parallels to the ballad's infanticide plot that exist in other European cultures. And talking of Iceland- I recently discovered that the traditional Icelandic Santa Clauses are known as the Yule Boys, Yule Lads, Yule Men, or Christmas boys (apologies to anyone from Iceland- this isn't something that's known to people on other sides of the world) BTW, this story proves that some stories are common in countries on the same continent.