Should definitely be charged. When one discharges a firearm there is a responsibility to identify one's target, not merely to have a notion, as well as to identify what else is in the line of fire.
Reminds me of the bowhunter in California who was shot out of his tree by a man who mistook him for a squirrel. I'd be afraid a squirrel that size might well come down from the tree and rip off my arms if shot. (Not to mention, movement in a tree might well be an endangered hawk or eagle.) Similarly, in an area I used to hunt some city folk had a "brush shot" during a buck-only hunt. They struck a man who had just retired at 58 in the femoral artery, too high to get a tourniquet. He bled out on Lifeforce - by the time he was picked up, his veins had collapsed and they could not get an IV started.
People with guns need to positively identify their targets, period. Hopefully this little girl survives and makes a full recovery, but far too many times there is no second chance.
