The 46-year-old is mum to son James Wilkie, eight, and twins Marion and Tabitha, two, and spoke about what it's like to be a parent at a New York screening of her new movie I Don't Know How She Does It.
She said: 'It's good to be scared. You should be! Love is scary and friendship is scary and children, even more so.'
She added: 'I remember laying in bed before my son was born, quite pregnant, thinking: 'I'm going to ruin him. The first thing I say to him that's meaningful is going to scar him for life. I'm going to mean to be helpful, and it's just going to destroy him, and he's going to spend the rest of his life flat out on a coach in a therapist's office.''