The Curious Incident of the Dog in the Night-Time, cycle 24 pages 105-120

In these 15 pages, Christopher continues to read the series of letters his mother has sent him. His father hid these letters to shield the truth about his mother. One of the letters contained the truth on why she left in the first place. She would have constant fights with his father because she couldn't cope with Christopher’s problem. The only person she felt that could help her was Roger, Mr. Shears. This relationship grew stronger as Mr. Shears grew apart from Mrs. Shears. Mr. Shears had a proposal, that they leave for London where they would be able to start a new life. Since Mr. Shears and Christopher’s mother fell in love, she decided that it would be better if she left. While reading these letters Christopher’s father walks in and freaks out. Christopher expecting a melt down receives a flood of apologies. He explains to him that he was going to tell him later and that it was a mistake, he just didn't want to complicate his life with more troubles. These apologies lead to a shocking confession. Christopher’s father was the one who killed Wellington.
Tether is a rope, chain, or the like, by which an animal is fastened to a fixed object so as to limit its range of movement. Saccades are the act of checking a horse quickly with a single strong pull of the reins.
Diary of Christopher:
I have recently found that my mother is alive. She didn’t really die of a heart attack. My father has masked a lot from me, including that she had moved to London with Mr. Shears. Why would he hide all this from me? I know he didn’t want to confuse me, but it would have been nice to know. Some how I feel that my father should have told me. Another thing is I can’t believe he actually killed Wellington. Why did he do it? What was his motive? Why did he yell at me for sneaking around and investigating if he knew I would continue? He should have just told me all of this saving us loads of trouble.