It would appear that if the mother of the shooter was a responsible gun owner her nut job son wouldn't have had access to the arsenal of guns in the house.
I personally know someone whose child drilled out the lock on the gun safe, drilled through the lock on the ammo box, loaded a gun and shot himself with it..
Would you say that if the parent was "a responsible gun owner [his] nut job son wouldn't have had access to the arsenal of guns in the house." in this situation as well?
Do you know what the son's diagnosis was?
Do you know how mom stored her guns?
Why is what SHE owned an "arsenal" and what you own, not?
Do tell