The seeming ease with which the toddler fired the gun and hit something makes me wonder if a revolver was used, but it would need to be cocked to have the lightest trigger pull available. I have some doubts about this as it would be unnecessary and stupid to carry a cocked revolver; they're easy enough to cock with one hand while brandishing or you can use the double action trigger to cock and release the hammer in one long motion. That being said, someone with small, weak hands might choose a shrouded hammer design but I still think carrying a cocked revolver, even holstered, is inherently risky. Additionally, unlike semi-automatic pistols, revolvers are very forgiving if the person shooting them has poor or no technique.