Christopher has discovered his father is hiding letters from him that are from his mother but hasn't been able to read them yet. Christopher's Father leaves for a work emergency which gives Christopher a chance to read the letters while he's gone.
After Christopher's Father leaves, Christopher goes into his father's room and takes out the letters. After counting 43 of them, he begins reading them.
Christopher continues to read letters until he discovers one where his mother says that she left Christopher and his father to be with their neighbor Mr. Shears. Which is news to him because he was told by his father that his mother died from a heart attack.
As a reaction to reading this Christopher becomes overwhelmed with emotions and curls into a ball and feels sick. Then he blacks out.
Christopher's Father comes home and discovers Christopher has read the letters and has vomited on himself. Christopher's Father instantly start apologizing for keeping the letters from him and for lying to him, but Christopher is unresponsive.
After bathing Christopher, and offering him something to eat which he remains unresponsive to, Christopher's father puts him to bed. He continues to try to explain himself and the decisions he's made but receives no reaction from Christopher. Christopher's Father confesses to killing Wellington which leaves Christopher more scared then he's ever been.