Hi there, I'm new to this forum but wanted to get some advice on my 18 week old cocker spaniel Ollie. Ollie is an attentive and intelligent boy who learns quickly, is good with other dogs and other people, but who has tended to get a bit cheeky with myself and my partner at times in terms of pushing boundaries and being more mouthy than he should be at this age - when excited he takes to lunging and snapping at us to get a response; we squeak loudly to show he is hurting us, tell him firmly 'No', ignore the behaviour as best we can and then if it continues we carry him to his crate for a few mins time out. More recently he has taken to resource guarding especially prized bones; he growls and if you even say his name from the other side of the room, or walk by him he barks aggressively. This came to a bit of a head yesterday when he lunged for arm as I sat 1 meter away from him in a bid to try to desensitize him to our presence at these times. He bit down hard and I responded by telling him 'No' and moving him away from his bone..I tried to take him through to his crate for time out but he went into a complete frenzy of barking and lunging for me and there was little I could safely do. I moved slowly away from him and he went back to his bone. I'm really kind of devastated by what happened - I didn't know that he had it within him to respond so aggressively. I'm obviously going to ensure he doesn't get this kind of bone again as he gets so worked up about it, but I'm just wondering what I should have done differently then, or what I should do in the future should a similar scenario arise. At the time I felt I had to take him away as a sign I would not tolerate his bad behaviour of biting me and to show him that this sort of behaviour would not 'work for him', but of course this set him off even more. And then when I had to move away after his frenzied response I feel like he has 'learned' from this that he can act like that to get what he wants (of course he went back to the bone) and that this is what he can do in the future. We have already tried the swapping valued treats for a handle of the bone method, and this worked previously, but things just got way out of hand so suddenly yesterday.