The eldest is 15. Certainly old enough to be left in charge. We don't know anything else about the background of this family. As I've said a zillion times before, it's not fair to assume the parents did something horribly wrong. Sometimes people just do bad things for very bizarre reasons....when a 30 year old kills someone, do we immediately start looking for the parents? And this stuff has been going on for centuries, I remember a similar incident that happened in my neighborhood when I was a kid in the late 50's. News just travels faster/further these days.....