I am awake at four A.M., along with other parents of drug-addicted children, children who are—we don’t know where. It is another interminable big-moon night. Suddenly I think, It’s Nic’s birthday. Today my son turns twenty. I fight off stabbing urges to second-guess myself. There must have been something I could have tried. I should never have let him leave. I should try to find him.