Later in the day, the kids go hiking in the woods. Duffy loses his jacket, and Andrew has a strange feeling that they’re being followed.
That evening, Andrew’s mom and aunt leave to get supplies, and the children are left alone. Suddenly they hear a scratching at the door. Duffy looks out the window and sees something huge. The children run to the barn and back to the house while the big creature chases them. Eventually they find themselves cornered in the house. The Sentinel comes through the door, throws Duffy his jacket, and says, “You forgot your jacket, stupid.”
The narrator tells us that this event made such an impact on Duffy that he hasn’t forgotten anything in over a year. We discover that sometimes bad habits can cause big problems.