During that argument, the youngest of the teenage girls in the home, only 14 years old, had found and loaded the 9mm pistol.
So she was 14, so what? She clearly understood that she should go for the pistol while the older sisters manned the rifles.
She reportedly fired in the general direction of the two men, scaring them off.
Now I see the problem. She's clearly old enough to know better, but young enough there's time to fix her gun control problem.