Among The Hidden
I just finished the book so here's how close to the end is. Luke was flashing his signal to Jen, another shadow child. But every time he flashed the signal she wouldn't signal back, so Luke had no choice and broke into her house. Thinking " Is she still at the rally." So he is using the online illegal chat room and now one is chatting back. Then he here's a loud man's voice saying "Who's in my house?" Luke finds out that the man's voice was Jen's dad, and Luke spills out everything. When Jen's dad start's crying Luke finds out that Jen died. A government worker shot all 40 shadow kids. Then he hears a loud knock at the door and he is saying " Population Police, open up."So Jen's dad throws Luke in the closet and the door breaks open and the Population Police starts looking around and looks in the closet... Read the book to find out the rest.