Here is a quote from the article that may explain part of it:
The 4-year-old cannot be held criminally responsible, but charges may be filed against the parents or others who left the gun within reach, police said. The mother, Jennifer Brice, also could face charges for leaving the children at home without adult supervision.
(edited, maybe thats not somthing people need to know about trigger locks) lol...
I have 3 rifles and I keep no ammo, I buy it as a need it, and I keep the guns on a rack down stairs... Im going to be looking into a locker soon... but I dont have any ammo for them so they're basicly useless (and they all have a trigger lock, just incase)
In itself a handgun is inherently NOT dangerous, but when in the hands of a person that has intent to cause harm it becomes a danger.
The whole issue on gun control is too touchy, both sides make good points and no happy medium can ever be reached.