I’m not talking teaching firearm usage & safety to children, & perhaps 5 is a bit early to start that. There’s responsible gun ownership & respect for firearms & teaching one’s child or children how to properly aim, fire, clean & store them.
There’s also idiotic & careless ownership & storage of such weapons. That the weapon was someplace the dead 5 year old could “play with it” shows this is the latter. Idiots!