"The Summer of the Swans" explores a young girl's coming of age when she faces the disappearance of her younger brother and realizes her own petty concerns pale in comparison to life's real and harrowing events. When Sara finally locates Charlie, she realizes the importance of meaningful, loving relationships.
Fourteen-year-old Sara Godfrey complains frequently about "the worst summer" of her life. She is not pretty enough, her feet are too large and she can't get over an unjust grudge against a boy named Joe whom she has falsely accused of stealing her brother's watch. Her brother, Charlie, is a mentally challenged 10-year-old who cannot speak but does understand much of what is said to him. He is a loving child, dependent upon his family, especially Sara, to take care of him.
Sara does love Charlie but her own selfish concerns get in the way of providing him the emotional care and support he needs. She spends much of her time fretting over the way her body looks and resenting her older sister for being prettier.
The children's mother is dead and their father works out of state, so they have been living with their Aunt Willie for years. The aunt provides food and shelter, but is largely ineffectual in their lives. For this reason, Sara has tried to step into a motherly role for Charlie, but her own immature, self-centered behaviors often get in the way.
When a bevy of swans appears on a lake close to the nearby woods, Charlie is fascinated by them and he eventually wanders off into the thicket, becoming lost. This is the turning point in the novel, when Sara panics at the thought of losing Charlie and suddenly realizes her love for her brother is much greater than the childish concerns she has had about her own appearance.
In the end, Sara locates Charlie, with the help of Joe whom she has forgiven, and she now feels much older and wiser than her 14 years.