Not many stories like this end with a good outcome and this one did through pure chance, I suspect.
Given the close proximity to his home, I believe this little boy was so exhausted that he just happened to sit or lie down where he was found; any further wandering would have led him to his demise.
So, that's all the good from this story.
The responsibility lies with the parents for letting him wander off in the first place. Yes, their anxiety would deserve empathy, but their negligence deserves that they apologize to all the people who had to put themselves out in the woods due to their stupidity and lack of attention to their son.
I'd test them for alcohol and drugs to determine if they warrant being charged. If they are cleared, they need a stern warning that this never happen again.