How does Mrs. Dean describe the histories of Wuthering Heights and Thrushcross Grange in Chapter 4?

The Linton family once owned the Grange, and the Earnshaws owned the Heights; Hareton Earnshaw, the coarse youth at the Heights, is the nephew of the late Mrs. Linton. Mrs. Dean asks Mr. Lockwood how Catherine looked, and about the behavior of Mr. Heathcliff. Mrs. Dean relates the story of Mr. Heathcliff’s past and how Hindley Earnshaw once brought a small dark child home.