What does Mrs. Dubose say about the children's mother and what is Jem's reaction in Chapter 11 of To Kill a Mockingbird?

Although old Mrs. Dubose is highly critical of Atticus and both of his children, she has nothing bad to say about Jem's and Scout's mother. Atticus's wife died from a heart attack when Scout was still a baby, and Mrs. Dubose remembers that "A lovelier lady than our mother never lived." Mrs. Dubose thought that Atticus should have remarried since it was "heartbreaking the way Atticus Finch let her children run wild." Jem's reaction to the sick, old lady's remarks?

... he went livid when Mrs. Dubose shot us this message.  (Chapter 11)

Jem later took out his anger on Mrs. Dubose's prize camellia bushes, but it was her remarks about Atticus "lawing for niggers" that was the final straw.

(These quotes can be found on the second page of Chapter 11, page 100 in my old paperback from 1982.)

What does Mrs. Dubose say about Jem and Scout's mother and how does Jem react?

At the beginning of Chapter 11, Scout mentions that Mrs. Dubose would continually insult them and their father any time they passed her house. Mrs. Dubose says that she pitied Atticus after his wife died. Mrs. Dubose comments that their mother was the loveliest lady who ever lived and it was heartbreaking to watch Atticus let his children run wild. Scout goes on to mention that she didn't remember her mother, but Jem did. Anytime Mrs. Dubose would bring up their mother Jem would become "livid." Jem loves his mother and would occasionally tell Scout stories about her. Jem becomes extremely defensive whenever someone brings her up, especially Mrs. Dubose. Mrs. Dubose's comment about Jem's mother hurts him deeply, and Scout can easily see that he is furious. One Saturday while the children are walking to the store, Mrs. Dubose makes several derogatory comments about Atticus and says if Jem's mother were still alive, their family would not have come to such moral degeneration. Her comments about Atticus and his mother send Jem over the edge, and he retaliates by ruining her camellia bush.

Mrs. Dubose compliments Jem and Scout's mother. She says that there was no lovelier woman than Mrs. Finch.

Unfortunately, Mrs. Dubose adds a negative comment after she praises Mrs. Finch. She remarks that the manner in which Atticus raises Jem and Scout is "heartbreaking" because he lets his children "run wild." When Jem hears this derogatory remark, he becomes greatly angered. However, in his usual sanguine manner, Atticus ignores this insult, instructing his son to do the same and also to be considerate because Mrs. Dubose is old and ill. Whenever Atticus passes Mrs. Dubose's house and she is outside, he tips his hat and compliments her, saying, "Good evening, Mrs. Dubose! You look like a picture this evening." Not only does Atticus have a complimentary greeting for her, but he also provides Mrs. Dubose with the courthouse news. After doing this, Atticus wishes her well for the next day. He swings Scout to his shoulders, and he and his children continue toward home. Scout comments that at such times as these, she feels that her father is "the bravest man who ever lived" (chapter 11).