I was gonna say a smartness remark about how apparently he realized at a very young age that killing the neighborhood pets wasn't doing it for him...
After reading how it all went down, something out of that kids control caused him to act this way... This sounds more like a product of a ******, abusive home life, rather than a sick, demented, evil kid.
Very sad. RIP to the young boy and I hope the other young boy can get the help he needs and grow up to be a comfortable, safe member of society.
Jmo.