Negligent? Yes, but as stated, not a reoccurring theme for the gun owner.
Charges? IMO, no. The mental anguish will do more than any sentence would.
Having not posted often on this site, allow me to introduce myself: David from NW Arkansas, pro-gun, pro-SD/HD, pro-stupid people outnumber even the semi-intelligent.
I work at a store as a sales clerk that sells long guns and I can say with professional certainty that the first thing people do when I hand them a firearm is jam their finger toward the trigger only to be stopped by a trigger guard I installed. Not all of them look directly into the muzzle but do not think for a moment that less than 20% of them do. To top things off, it isn't uncommon for the muzzle to be pointed at someone (usually me) during some of the firearm viewings. Are the guns unloaded, absolutely. I first ensure firearms are unloaded upon receiving from the factory, then prior to installing a trigger lock, then again in every instance before handing one to a customer, it has become pure instinct for me at this point (Their are even a few "gun nuts" that even check for themselves after being handed the firearm
). If not in my hands or the customers hands, they are behind lock and key. Some might even say I go overboard by only allowing one gun to be out of the case at a time... and to those people, I say open your own gun store and do things your own way... As for me, I make it a point to ensure my own safety as well as anyone in my presence and have decided this is the best route for me.
Having said all of that, I like to think I am doing everything in my power to be as safe as I can and I follow a lot of these procedures at home as well as at work. To the point of the OP, I fully believe I am not the smartest person alive yet I know from watching people, I exhibit better gun safety than a lot of people. (Not being elitist, attempting to make a point) As I said, I'm no smarter than anyone, I think being taught gun safety from an early age is the sole reason for my safe habits. I encourage children even from non-gun households to know gun safety... It isn't stated in the OP whether the girl that fired the gun was from a non-gun household or not but supposing she was, gun safety education could have changed the outcome (maybe not the case, just showing why I think it is important for all children, not just gun friendly households.)
I also would like to say that at 14, I knew guns were dangerous. I also knew at 14, that tobacco was bad for you. (Actually, I have been told both from about the age of 5). Did I still start using tobacco at 18? Yes. I say this to point out that A) I would like to think that 14 year olds knowing guns are dangerous isn't the minority and B) People are stupid. Knowing it was bad for me, I still started using tobacco. Education was a great start but "do as I say" didn't scare me away after watching dad smoke a pack of cigarettes a day. You can stress safety orally until you are blue in the face
but acting in unsafe ways will only overrule those lessons and instill the fact that accidents only happen to others. Even if you don't think anyone is watching and learning from your actions, you never know. (Not to mention your own safety is at risk even when others aren't watching you) Don't just say, DO!