I know this might not sound too good but have you considered having your son evaluated for ADHD? I'm asking because your son sounds like what used to be a carbon copy of my youngest brother. Especially how he treats your animals and his own brother. ADHD promotes severe impulsivity in children where they do everything on impulse only with very little thought process and almost no follow-through. They are like walking festivals on two-feet and usually the sounds of crash, bang, boom, and screams follow them through the house! Discipline will work but only to a point because it is hard to get these kids to calm down and focus on what you want them to do. They are very busy and always up to something.....usually of the mischievious kind or even mean and destructive kind. This is how I described my youngest brother until my mother took him into the pediatrician and told the guy that enough was enough. He would hit, punch, bite, pull hair and just physically torment our dogs and even us older siblings. He was noisy, disruptive, and always going Mach-90 all throughout the house. Trust me.....my parents knew all about discipline and how to dole it out. This was NOT a discipline issue, it was a whole other ballgame with my brother. He was evaluated and diagnosed with ADHD and was put on medication. Back then, he took Ritalin once a day. Lo and behold....what was was a nightmare on wheels turned into a calm, loving, funny, and courteous little boy....one that I actually liked to be around and call my brother! ADHD is a chemical imbalance and can't be helped by the child. It just is what it is and like anything else that is a medical problem, if you don't treat it, it spirals out of control and everyone will suffer. My brother was helped by this diagnosis and this treatment immensely. He remained on Ritalin until he was 13 and was able to really cognitively control his impulsivity and govern himself correctly as he grew up. Once you have ADHD, you always have it and it is a struggle...even as an adult he has to focus harder and make a conscious effort to maintain composure and not make snap decisions or fly off the handle at people. When he does act up, we know why and we take it into consideration. Sometimes we point out what has happened and other times we already know he notices his behavior and an apology will follow shortly. Your son sounds like he may have ADHD and if he doesn't, then there are some serious consistency issues with discipline and expected behavior in your house. If you have other kids and they do not act like him, I would suspect ADHD and get this looked at right away. It is not the end of the world if he has it and don't blame yourself. The sad part is doing nothing and letting this behavior of his escalate....and it will. When he starts school, if he acts like this to other children and teachers, you will be in for a long and very harrowing school career. Do something now and see if he can be evaluated by your pediatrician. If he doesn't fit the criteria for ADHD....you need to look at your parenting style and skills and be ready to make an abrupt change to get the results that you need and want. I hope this helps. I know exactly what you are seeing and feeling because I lived this as a sibling....it is not funny.