The Case of the Wailing Woman (4)

"So, what do we know thus far?" Arven asked his two companions.
"We're facing a supernatural fairytale who likes to kill people who are isolated and alone. We have no evidence to inspect, and not enough victims to even consider trying to form a pattern!" growled David.
"Not to mention her apparent ability to phase in and out of reality, so there's no way to track her!" conceded a disheartened Arven. "This is a fools errand"

"Guys! Stick to facts. We've faced worse than this, remember the whole Vakarian incident? This creature kills it's victims through fear. Why? We need to establish motive. Does it target victims for sustenance? Sport? Some form of revenge?" said Susan, ever the voice of reason.

"You're right!" Arven agreed, beginning to bristle with confidence again. "Damn right I am!". "I'll run down to the library and check for historical cases matching this MO in the news archives."  David announced, also feeling buoyed up. "That's more like it! Susan and I shall pack for the trip to Tom's childhood home. Meet back at the Red Tavern by 4pm.!

It was about 5pm by the time the group of four reached the marshlands. During the trip, David informed the group that he had discovered an odd pattern in some of the old newspapers. Every 7 years, there were 3 high profile reports of deaths involving "Screams or other unexplained noises", and each triplet of deaths happened within a week of each other. He insisted that it was not a concrete pattern, as the reports were from differing papers, with little corroboration, and the search parameters were hardly rigorous. Still, 3 & 7 were curiously important numbers in Irish folklore, and they didn't have any other leads to go on. In addition, there seemed to be a worrying trend of larger scale destruction in the wake of the third victim. This ranged from a family found dead in the earliest records, progressing to a bus crash, and most recently a school fire with many casualties. "Whatever schedule this Banshee is following, it's growing in power!" warned David.