Atticus rarely has a bad word to say about anyone, but the Ewells are an exception. He describes them best when he tells Scout that
... the Ewells had been the disgrace of Maycomb for three generations. (Chapter 3)
One can only imagine what Bob's father and grandfather must have been like since the present Ewell patriarch is positively the most evil character in the novel. Bob does not have a job--"None of them had done an honest day's work in his recollection," says Atticus--and drinks up his welfare check instead of providing for his children. He spends most of his time drinking and hunting out of season. Described as a "little bantam cock of a man" who bore "no resemblance to his namesake (Confederate hero General Robert E. Lee)," he absolutely gloats when giving the untruthful testimony about Tom Robinson raping his daughter. Tom's and Mayella's testimony actually suggests that Bob had beaten Mayella--and possibly even had other improper relations with her. Later, unsatisfied that Tom has been found guilty and faces the death penalty, Bob stalks the people he most despises--Tom's widow, Helen; Judge Taylor; and, apparently, Atticus's own children. In the end, he attempts to make good his threat to get even with Atticus "if it took the rest of his life." Sheriff Tate practically rejoices when he finds Bob's body: Bob
"... wasn't crazy, mean as hell. Low-down skunk... (the) kind of men you have to shoot before you say hidy to 'em. Ewell 'as one of 'em." (Chapter 29)
Appropriately, the family lives in an old cabin adjacent to the town dump: it is author Harper Lee's way of inferring that they are "white trash" without ever using the term. Bob's wife is dead, and he pays little attention to his children, instead allowing his oldest daughter, Mayella, to keep watch over them. The children are filthy, lice-ridden and illiterate.
They were people, but they lived like animals. (Chapter 3)
Burris--"the filthiest human I had ever seen"-- crudely curses and threatens his first grade teacher, Miss Caroline, calling her a "snot-nosed slut." Mayella, who does arouse some sympathy from Scout (and the reader) because she tries more than the other family members to provide a bit of beauty in the household with her lovingly-tended geraniums, nevertheless sinks to her father's level when she backs his story that Tom had raped her. Mayella comes across as both pitiful and untrustworthy, and
I guess if she hadn't been so poor and ignorant, Judge Taylor would have put her under the jail for the contempt she had shown everybody in the courtroom. (Chapter 18)