How quick come the reasons for approving what we like! Lady Russell had another excellent one at hand, for being extremely glad that Sir Walter and his family were to remove from the country. Elizabeth had been lately forming an intimacy, which she wished to see interrupted. It was with a daughter of Mr. Shepherd, who had returned, after an unprosperous marriage, to her father's house, with the additional burden of two children. She was a clever young woman, who understood the art of pleasing -- the art of pleasing, at least, at Kellynch Hall; and who had made herself so acceptable to Miss Elliot, as to have been already staying there more than once, in spite of all that Lady Russell, who thought it a friendship quite out of place, could hint of caution and reserve.
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From situation, Mrs. Clay was, in Lady Russell's estimate, a very unequal, and in her character she believed a very dangerous companion; and a removal that would leave Mrs. Clay behind, and bring a choice of more suitable intimates within Miss Elliot's reach, was therefore an object of first-rate importance.(Ch. 2)
In chapter 3, when Mr. Shepherd is speaking with Sir Walter about the possibilty of letting Kellynch to a naval officer, Mrs. Clay intervenes in the conversation.
Mrs. Clay was present: her father had driven her over, nothing being of so much use to Mrs. Clay's health as a drive to Kellynch (Ch 3)