The father's injury, in this case, can be connected to guilt at having been away. He was not there for his father.

The horrors he saw but could not prevent, as well as some he may have directly participated in -- it can create tremendous psychological pressures that can manifest.

The most important issue is the climate of the school. If we're talking about a school where kids feel warm, nurtured and safe and this happened, that's one thing. If we're talking about a school with lots of tension, that's another.