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If your daughter was misbehaving around other individuals as well, then I would suggest that she may have a hyperactivity disorder, However, since she is selective in only behaving inappropriately with you, that is ruled out.
The arrival of the baby has caused your daughter to feel disconnected with you. The only way that she can express her feelings is to show aggressiveness and out of control behavior. Her aggression cannot be erased by time outs, enforcing logical consequences, or reasoning.
What you need to do is to first reconnect with your daughter. Be close to her. Have more fun playtime where your daughter can laugh alot. Listen to your daughter more if she can verbalize her thoughts so she can release her feelings. Also, try to catch her misbehavior before it rises and intervene.
She wants you. She really needs you. She feels tense, frightened, and isolated. She craves the attention that she had before the baby arrived. Forget about all of the inappropriate behavior and start off fresh tomorrow. Your daughter can be that angel that she once was.