My 4 year old DS has turned into an absolute nightmare over the last 4 months and I'm really struggling with how to deal with it. So far I have been taking his treats away throughout the day like no TV for the rest of the day, no pudding, straight to bed after dinner, time out, naughty step and have started a reward chart 3 days ago which doesn't seem to be working. He throws the most horrendous tantrums and can be so nasty to our 4 month old dachound yet lovely to his 2 week old sister. He never shares his toys with his cousin and back chats me something chronic. I am at the end of my tether and feel like I'm always telling him off or shouting at him. He just never listens to me! Any advice at all? Feel like I've tried everything and none of it is working, worried I'm going to start disliking DS.