What do readers indirectly learn about the home life of the Ewell family in To Kill a Mockingbird?

The Ewells are very poor and live outside the law, eschewing school and society.

From Burris Ewell, we learn that proper hygiene is either not available or not a priority for the Ewell household.  He has head lice and is generally unclean in his appearance and his manners.

He was the filthiest human I had ever seen. His neck was dark gray, the backs of his hands were rusty, and his fingernails were black deep into the quick. He peered at Miss Caroline from a fist-sized clean space on his face. (Ch. 3) 

The Ewells also do not value education.  This is why their children cannot read or write, and only go to school on the first day of school and then stay home for the rest of the year.  Burris doesn’t even make it through the whole first day.  He gets into a fight with the teacher when she wants him to go home and wash his hair and calls her a “snot-nosed slut” (Ch. 3).  It is his third first day of first grade.

Atticus has his own perception of the Ewells, which he describes to Scout when she is impressed with the fact that they do not have to go to school or obey the laws.

They were people, but they lived like animals. “They can go to school any time they want to, when they show the faintest symptom of wanting an education,” said Atticus. (Ch. 3) 

Atticus says that Bob Ewell hunts for his food even when hunting is out of season because he spends his relief checks on alcohol.  He hasn’t had a job.  He can’t keep a job.  After the trial he is said to be the only person Maycomb has heard of who has been fired from the W.P.A. for laziness. 

When Bob Ewell and Mayella Ewell testify, the sad state of their lives is described.  Bob Ewell beats Mayella, and may possibly sexually abuse her.  He leaves her in charge of the many children (how many is never clear), with hardly anything to feed them, and never lifts a hand to help her take care of them.  She doesn’t seem to understand what Atticus means when he asks her if she has any friends.  There is no beauty in her life except for the flowers she keeps, and the only person she has to keep her company is Tom Robinson.  Unfortunately, being around him is considered wrong by Maycomb society, because he is black and she is white.