For anyone who has been digging or wants to dig on the psychologists of mass shooters, it seems like most of them focus on children. Maybe thats obvious simce most of the shooters are kids, but anyways their practices all seem to focus on "family" and more specifically "children." Behavioural inhibition problems also seems to come up a lot.

Will source digs more thoroughly later on just thought I'd post what I've found so far.