What is Mrs. Higgins's attitude towards Pickering and her son in the opening of Act V, and what do her reactions reveal about her character?

As a mother, Mrs. Higgins lets her son live his own life. That doesn't mean she doesn't offer advice or neglect to tell him when he is wrong. She does not agree with him just for the sake of it or to keep the peace. She goes her own way in the same way Henry does, but she never backs down, and she never allows him to intimidate her. Mrs. Higgins is more grounded and sympathetic to Liza than her son is.