Watch "The Sleepover."  It's awesome. 

"Detention" had an awesome take off of the phone call by having the killer text the victim before slashing her-- a second after she received it.

I feel like the reason we see a lot of the family issues thing is because the idea that someone became a sick and crazy bastard because of how terrible the world is just takes too long to set up.  "My mother hit me, so I'll kill you" is much quicker and no one questions it.  Which maybe they should.