What does Christine find in her house that makes her decide to trust her husband in Part 2: The Journal of Christine Lucas, November 21?

Christine finds the key to the locked box of pictures Ben had hidden in his office. Christine opens the box and looks through the pictures, finding pictures of herself and Ben on what must have been their honeymoon, pictures of Adam, pictures of Claire at her wedding, and a newspaper clipping describing Adam's death. Christine decides that all this should convince her to trust Ben.