Lindsay Lohan is planning to take out a restraining order on her father.
The 'Mean Girls' star - who recently claimed dad Michael should be "on medication" to stop him publicly shaming her - is said to be "terrified" the 48-year-old will harm her.
A source close to the 22-year-old star said: "Lindsay is going to take out an order of protection against Michael. He is behaving so erratically that she's terrified he'll do something to her. She's contacted her lawyer to arrange this."
Michael - who has three children, Lindsay, Ali and Cody, with ex-wife Dina - has also driven away the rest of his family with his behaviour and attitude.
The source added to the New York Post newspaper: "Ali already has an order of protection against him, as does Dina. No one is speaking with him until he gets help."
The pair's troubled relationship came to a head recently when Michael accused Lindsay's girlfriend Samantha Ronson of "using" his daughter for publicity. Lindsay, in turn, called Michael a "public embarrassment and a bully".
Most recently, Lindsay wrote on her MySpace page: "My father obviously needs to be on medication to control his moods.
"He is out of line and his words show how much anger he has, and it's dangerous and scary as it reminds me of how he treated my mother and I my whole childhood. He needs to be stopped.
"This is yet another reason why we aren't speaking."
