What is the significance of the seventh son of a seventh son?
In the Middle Ages, the Seventh Son of a Seventh Son (or
sometimes just the Seventh Son) was believed to be born a werewolf.
The Seventh Daughter was believed to be a witch. This led to the
killing of many Seventh children until the myth died out. However,
another belief was instead of becoming a werewolf, the Seventh Son
of a Seventh Son would be gifted in some way, more in-touch with
the Unseen World, for example, the ability to see faeries or speak
to the dead.