Seventh of a Seventh

You know that old legend "the son of a seventh son"? The wives tale goes that seventh son of a seventh son will have special healing powers only if he is in a line of all males, no female can break the chain. Here's an interesting story, my father gets horrible sores in his mouth. He's had up to 19 at once (and that was on his wedding day!). Well, when he was a child he knew a woman who was the seventh of a seventh. I know technically a female line of seventh doesn't match with the legend, but to this day my dad swears by this. By his accounts he remembers that the lady didn't ever talk. She just healed people. His mother, who was a nurse, took him one day to this lady and she stared him down, grabbed his head, cranked open his mouth and gently blew into his mouth. He was astonished and thought it was all hogwash, but the next morning he woke up with no sores and they didn't come back for months! I'm betting I'm not the only one with one of these stories either.