Books in the Hackers series

Chris Alten was a 13-year-old athlete until a car accident kills his father and leaves Chris confined to a wheelchair. His world has suddenly shrunk in size and he cannot adjust to the changes. He takes his frustration out on his mother and his friends.  Then he meets a new friend who seems to know everything about Chris. Although Harvey is mysterious, Chris begins to open up and once again be happy.  Then he and another friend, Ashlyn Jacobsen, discover Harvey is an artificial intelligence program created by Chris's dead father. Alive or not, Harvey still proves himself a friend to both Chris and Ashlyn.  Chris learns that cyber-terrorists killed his father searching for Harvey, and they are still searching for the program. Their hunt begins in cyberspace. There, Harvey is near all powerful and Chris can walk, but when the hunt moves into the real world, Harvey is powerless and Chris is crippled.  Chris and Ashlyn must decide whether preserving a computer program is worth the risk against cyber-terrorists who have show they are willing to kill.