Well.. There are 6+ billion people in our world. Surely something like this has happened somewhere at some point in time, maybe not even once. Thats why I always stay away from overly sad and psychological shows - they always leave me thinking that something similar might've really happened to someone. :/
In fact, I've read that the last episode of School Days was cancelled on many stations because some 16-year-old girl killed her dad with an axe not long before the episode was supposed to be aired.
Source.