Please,please don't be put off cockers by this! Several years ago, my first cocker, a blue roan went through a similar thing. He was terrible - difficult to train, quite dominant etc. He bit three people in quick succession, and my male GSD was terrified of him. He used to 'attack' for no reason, grabbing Max around the throat and shaking him like a rag doll. It was extremely frightening to watch, and after the last attack, I took Jasper (cocker) to the vet, and asked him about behaviourists, because his behaviour was becoming so extreme. My vet (who I found out long afterwards hated cockers) told me that a behaviourist would be no good, because Jasper was exhibiting rage syndrome, and my only option was to have him PTS. I was in bits, but the vet told me in no uncertain terms that if Jasper bit a child or something like that, I would be ordered to have him destroyed. I very reluctantly listened to what he said, and agreed that having him PTS would be the best thing. Oh my God, how much I have regretted it since that day, having a young dog destroyed, and my entire family heartbroken. With hindsight, I do not believe that Jasper had developed rage syndrome, and the guilt I have now lives with me forever. I have since got another cocker, William, who is six and a half, and he is a fantastic little dog, although he does get very possessive with his toys and warns my GSD off in no uncertain terms. Hindsight however, is a wonderful thing. Please listen to all on here when they say that true rage syndrome is very rare. Cockers are fantastic!