In Gennifer Choldenko's Al Capone Does My Shirts, Moose Flanagan moves with his family to Alcatraz Island where his father gets a job at the prison. Moose says:
The convicts we have are the kind other prisons don't want.
Moose's sister, Natalie, has autism. She is sixteen but her mother says she is ten. It is hard for Moose to have a "normal" life because he cares for Natalie while his father works and his mother gives piano lessons, but he is a good brother. To help Natalie, Moose's mother hopes to get Natalie into a private school.
Subplot: the warden's daughter, Piper, has come up with a scheme to have famous inmates launder clothing for the kids at school—for a fee. Al Capone happens to be one of the notorious criminals at Alcatraz.
As a side note, while Capone was a cold-blooded criminal (though he was only ever convicted of tax evasion), he was surprisingly generous to several needy causes. For a man whose empire was worth approximately $62 million dollars, one wonders why he would bother.
...[Capone] had become a highly visible public figure. He made daily trips to City Hall, opened soup kitchens to feed the poor, and even lobbied for milk bottle dating to ensure the safety of the city's children.
Soon Natalie is placed in the private school, but she is forced to return home. More than ever, Moose must constantly be with Natalie; soon he becomes afraid when she makes friends with an inmate. Moose tries to share his worries with his mother, but she will not listen. Spending extra time working with Natalie, Moose's parents hope she will improve and return to the school.
When it seems that Natalie will finally be able to enter the Esther P. Marinoff School, it is discovered that Natalie is not as young as the school had thought. Though improved, they cannot take a girl of her age.
Moose secretly writes a note to Al Capone, asking him to help Natalie. Piper slips Moose's note into the prison's dirty laundry...
Soon, there is news that a new wing has been added to the school. Natalie will be able to attend and the family is surprised, but thrilled.
No one has any idea why the director has had this sudden change of heart except Moose. His suspicions are confirmed when he puts on a clean shirt from the Alcatraz Laundry the next morning and finds a scrap of paper stuffed in the sleeve with a simple message: “Done.”
After reading the story, only then can one determine its tone. Tone concentrates totally on the author—it is defined as:
...the author's attitude toward his material, the audience, or both.
Identifying the tone can help the reader better understand the author's purpose in writing a story. We need to read between the lines to discover how the author feels about her topic/characters. Sympathetic concern for autism sufferers clearly seems to be one—and the difficulties of providing care. However, a second is the importance of family sticking together regardless of hardships.
Natalie comments on family at the start of the book, saying:
Natalie Flanagan's whole family.
This is a clue about an important element in the book. Moose finds it hard to have friends caring for Natalie, but he cares deeply for her, doing all he can—not only to keep her safe, but to (surprisingly) find a place where she can live to be more fulfilled. Moose's character strongly supports the author's tone in the story.