How does Nelly respond to Catherine's disobedience in Chapter 18?

After they leave, Cathy tells Nelly that she had been on her way to Penistone Craggs when one of Hareton's dogs attacked her own, and she was obliged to enter. Nelly tells Cathy that her father disapproves of the Heights and its inhabitants, and that she should never go there again, to which Cathy reluctantly agrees.