The shooting took place at 10:30 PM, but "No adults were home at the time." What could go wrong with a bunch of unsupervised eight graders at 10:30?
This is the part that got me-"We're told Neibel went looking through the house and found a 12-gauge shotgun." See comment above but when I was 13, I would have never "gone looking through" someone else's house.
I hate to say it, but looks like plenty of bad parenting to go around.