I have zero knowledge of the accused...but these attempted mass killing's seem to be flourishing.
I put it down to crappy parenting as much as anything. Scratch a deeply disturbed criminal and more times then not you will find lousy parents.
Far, FAR too many lousy parents in this world that have no business having children is a gigantic problem that few seem to either be aware of or even care about.
Socially speaking, raising children should be considered a privilege...that few have the skills to properly undertake.
As it is, nobody seems to think twice when obviously troubled people have children. Like having a child will 'settle down' people.
I truly believe that too many people look at children as diversions/goals/glorified pets instead of sentient human beings.