The Curious Incident of the Dog in the Night-Time has two major reveals: Christopher’s father killed Wellington and Christopher’s mother is alive. Haddon provides clues that foreshadow these facts to the reader, but Christopher himself is incapable of understanding the clues until they are explicitly presented to him.

Christopher’s Father Killed Wellington

Christopher’s father has a strong, seemingly disproportionate objection to Christopher’s investigation into Wellington’s murder, foreshadowing that Christopher’s father killed Wellington. Christopher uses his knowledge of mystery novels, particularly the stories of Sherlock Holmes, to deduce that Wellington was probably murdered by someone who knew him, a category that includes Christopher’s father. Christopher’s father forbids him to investigate the murder, claiming Christopher needs to stay out of people’s business. At first, this command seems like good advice for Christopher, especially after he is arrested for striking a police officer. Over time, however, his father’s opposition becomes extreme and violent. When Christopher’s father lashes out, throws away his book, and strikes Christopher, the reader suspects Christopher’s father knows more about Wellington’s murder. However, Christopher’s father loves Christopher, and his short temper comes from a place of frustration and a desperate desire to protect his son from discovering the tangled relationship between himself, Mrs. Shears, Mr. Shears, and Christopher’s mom. When Christopher’s father admits he killed Wellington, the reader sees his act of violence as another manifestation of pain, a culmination of misguided attempts to protect Christopher from the truth.

Christopher’s Mother Is Alive

Details of Christopher’s parents’ marital problems and the odd circumstances surrounding his mother’s death foreshadow that Christopher’s mother is still alive. Christopher writes about his parents’ unhappy marriage, and the fact that his behavioral problems caused them to fight. He recalls his mother saying in response to one of his fits: “You are going to drive me into an early grave.” While Christopher’s behavior did not literally kill his mother, it did cause her to leave their family, which motivated his father to tell Christopher she had died. Even Christopher finds the details of his mother’s sudden heart attack confusing, noting that she was quite young and physically in shape. Furthermore, Christopher learns seemingly tangential information about his Prime Suspect, Mr. Shears: he and his mother had an affair. This revelation ties his parents’ marital problems back to the murder of Wellington, foreshadowing that the affair, Wellington’s murder, and news of Christopher’s mother’s untimely death are all related.