When you watch a scary movie, it's easy to console yourself by simply recalling that "it's only a movie." The same can't be said of these news stories that are terrifying enough to become horror movie plots. Take, for example, the cell phone stalker:
There’s annoying phone calls, and then there’s what happened to three families in Washington State in 2007. The Kuykendall, McKay, and Price families underwent weeks of harassment that went far beyond your typical obnoxious caller.
It started with 16-year-old Courtney Kuykendall’s phone sending texts to her friends that she didn’t write. Then she and her mother and father, Heather and Tim Kuykendall, began receiving disturbing phone calls at all hours from a raspy voice that threatened to slit their throats and kill their pets. This quickly turned even more terrifying when they discovered that the caller seemed to know when they were and weren’t home, who was in the house, what they were doing, and even what they were wearing.
The family began receiving voice mails that consisted of nothing but their own conversations being played back to them. After a talk with a police officer about the harassment, the caller sent the family a recording of the conversation. When the family installed a new security system, the caller was able to tell them the code.
Even odder, the majority of the calls appeared to come from Courtney Kuykendall’s phone, even when it was turned off. Not that the phone being off stopped the caller anyway, as he was apparently capable of turning the phone on and off at will.
Although the Kuykendalls got new phones, numbers, and wireless accounts on three separate occasions, the calls continued to come. The police admitted that they were baffled while the Kuykendalls’ cell phone provider, Sprint, claimed that the events they were describing were impossible. Experts have speculated that the calls might have been the result of some sort of advanced cell phone hacking combined with a close knowledge of the family.
While there are some theories of how the cell phone stalker worked in the comments at the link, the idea is creepy no matter how it was done.
Link
So, ya, Occam an all - It sure looks like someone in the family is doing it.