by Margaret Peterson Haddix
Luke has been in hiding his whole life because his existence is illegal in a society where parents are allowed no more than 2 children. He can’t leave the house to go outside and play, or to go to school. He can’t stand near the window in case someone outside might spot him. If his existence is discovered by anyone outside his own family, the Population Police will take him away. See also the other books in the Shadow Children series.