Kill switch / Chris Lynch.
Daniel simply wants to spend one last summer with his grandfather, Da, before his move to college and Da's dementia pull them apart, but when Da starts to let things slip about a secret life, Daniel must protect him from old "friends" who intend to make sure Da stays quiet.
New York :
Simon & Schuster BFYR,
Walker Library - Curriculum Collection - Juvenile - 3rd Floor
Pull and Hold