Just as background Our son was 4 in July. He started reception at school in September and has just had a sister who is a month old. Before this he was a loving and kind little boy who we would love being around. He now appears to have turned into Jekyll and Hyde. He tells us he hates us non stop and when we say no to something or ask him.to do something he doesn't want to then he becomes really angry - he will scream at the top of his lungs how much he hates us, he will try hitting himself or throws himself around and just screams over and over, it can be over really silly things, the other day we were leaving his friends house and he was fine until we got in the car and his friend said goodbye - my son got himself out and started refusing to come back - crying and saying 'i hate you and 'i hate your car' 'i hate home' until eventually he got back in. Tonight he got angry when my husband said he couldn't put his new electronic train In the bath, he threw himself around and ended up hurting his foot on the door - he then screamed and shouted further saying it was daddy's fault and that he hit him! When i said he hadnt and that he had thrown himself against the door, his reponse was still to tell us it was our fault. Then in the bath, he was told when we go to look at Christmas decorations tomorrow it is to simply look and not buy anything - with this he proceeded to hit my husband over and over, screaming how angry he is. He then got put the bath having not been washed so I put him back in, I told.him because he hit daddy his new train from nana and grandpops was going away in the cupboard. My son got extremely angry and started hitting me and himself and screaming over and over how much he hates us and how angry he is. He then threw a toy in my face which has caused a small bruise and slight bleeding. He was told no books or me staying with him until he sleeps tonight. I put him to bed and said goodnight. He has just stayed with my in-laws as a special treat for the beginning of half term and they said he was as good as gold but noticed when my husband picked him up that his behaviour changed and he wouldn't do as he was told . He is brilliant with his new sister and school have not raised any concerns (which I guess they would if they experienced this, in fact I asked and they said he is doing really well) so I am emotional and at a loss as what we have done wrong or what is causing this behaviour. Tonight I have been in tears with my husband as I feel like our loving boy has totally disappeared. He also said 'f-ing' several times tonight laughing which we never say at home so I also had to tell him not to say this. I am not looking for judgements just some advice or reassurance that we are not the only ones experiencing this behaviour. :( any advice?!