Irony is a literary device in which the opposite of what is expected occurs. A character may possess an unexpected attribute or behave in a way that is unexpected. Dramatic irony occurs when the reader is aware of circumstances about which one or more of the characters is unaware.
One of the most prominent examples of irony in The Story of Edgar Sawtelle is Edgar's proficiency with language. Born mute, Edgar is unable to communicate with others. His biggest struggle is that he cannot reveal the events he has witnessed or explain his actions. However, the irony is that he has a love and mastery of language that few others do. When he is given a litter of puppies to care for at his family's kennel, Edgar peruses the dictionary for the perfect name for each dog. His precise use of language is a means to exert control over one aspect of his life when much of his life is beyond his control. He is even able to train the dogs using sign language commands.
Another example of irony occurs through the character of Edgar's uncle Claude. After Edgar's father dies, his mother becomes ill and two of the dogs are injured in a fight. Claude appears to be their savior, caring for the dogs when they cannot afford a vet and nursing Edgar's mother back to health. The irony, however, is that Claude himself murdered Edgar's father and is attempting to seduce his mother. Edgar is the only one with any evidence of Claude's guilt, but he is unable to voice his accusations. When Edgar attempts to confront Claude, he unintentionally causes the death of an innocent man and must flee the scene.