My daughter has always been a great little girl. She's very intelligent and not yet at school. Starts this September. When she turned 4 last September I was 7months pregnant within a couple of weeks her behaviour just changed over night. Started being naughty not listening, shouting back get angry/crying a lot. Since I've had my second baby it has got worse. She's loving and she's not to him. It's like she gets over excited and shows off. The other day I put her in her room after she picked him up and dropped him she had a massive tantrum and the room was wrecked. She understands what's she's doing I personally think she is upset but i don't know what to do to break this vicious circle of behaviour. Please help x