Yes but Angus. I happen to know that in Iceland you build roads avoiding areas where elves live.
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So it's deeply rooted in your tradition. Here in Ireland we have no elves or trolls but heaven forfend anyone who interferes with a fairy fort or tree. That is what happened to the DeLorean Motor Company. They uprooted a fairy tree and look what happened next.
Still the kid is hard to explain. Although I imagine I could produce a hoax and coach a child into believing he was the reincarnation of somebody or other.