I think at the end of act 2 he was starting to wonder if his father was guilty or not. He started finding out stuff and hearing things from other people. I think he started wondering and then started to ask more questions about the situation. His father did kill the pilots and I think chris knew it by the middle of ActIII. He deffenitly found out though and he totally changed his mind about his father.

I think that she knew he was but she wouldnt except the fact that Larry is gone for good. Almost all through the story she seemed depressed alot and everytime the subject of Larry was brought up she would flip out and keep saying that he is coming back. She had to know he was dead just for the simple fact he had been gone for three years and had not wrote a letter to his family in that long of time.

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