Task: Question Answering
Input (English): Passage: In the 1940s, Deputy Waterhouse and Sheriff Proctor drive to a nearby quarry with two bodies stowed in their truck. Waterhouse takes a necklace off one of the bodies and they dump the two corpses into the water. Waterhouse then holds Proctor at gunpoint and demands he get rid of his badge, telling Proctor that he's no longer fit to be sheriff. Proctor throws his badge over the cliff.
In the 1970s, Jacqueline Mathers, called Jake, and her brother Sean head to the quarry. Sean insists she get over her fear of jumping into the water below and offers to jump with her. Sean jumps but Jake becomes scared and lets go of Sean's hand at the last second. Jake watches as her brother plunges into the water below but doesn't resurface. In a panic, she runs for help, tripping along the way and gashing her forehead, which leaves a large scar. Deputy Freeman informs Waterhouse, now the sheriff, that his grandson has drowned in the quarry.
Jake suffers from survivor's remorse and falls into depression. A boy at school named Willie Proctor, the grandson of the old sheriff, has a crush on her and draws her pictures, much to the disapproval of his grandfather. Some months later, Jake's parents tell her they're going to have a baby which upsets Jake. The next day, Jake runs into three gypsy brothers led by Wyeth. Wyeth tells her he has the power to bring her brother back but someone will have to die in his place. The brothers take her back to their cabin on Proctor's property and make a blood oath with Jake - they'll bring her brother back if she pushes Willie Proctor over the quarry edge. She agrees. When she returns home after dark, her parents question her about where she's been. She tells them three men took her to their cabin. Waterhouse takes Jake to the cabin and asks Jake to identify the three brothers but, remembering her oath, Jake says she's never seen them before. 
Question: Who is Waterhouse's grandson?
Output (English): Sean.