Task: Question Answering
Input (English): Passage: The Creed family—Louis, Rachel, and their children Ellie and Gage—move from Chicago to rural Ludlow, Maine, after Louis is offered a job as a doctor with the University of Maine. They befriend their elderly neighbor Jud Crandall, who takes them to an isolated pet cemetery (misspelled "sematary") in the forest behind the Creed's new home.
On his first day at work, Louis encounters Victor Pascow, a jogger who has been mortally injured after being hit by a truck. He warns Louis about the pet cemetery before he dies, calling Louis by name despite the fact they have not previously met. That night, Pascow comes to Louis as a ghost and leads him to the Pet Sematary, warning him not to cross the barrier because the ground beyond is "sour". Louis awakens, assuming it was a dream, but notices his feet are covered in dirt.
During Thanksgiving while the family is gone, Ellie's cat, Church, is run down on the highway. Realizing that Ellie will be devastated, Jud takes Louis beyond the cemetery and deep into the woods, where they reach an ancient Micmac burial ground. Jud instructs Louis to bury the cat and warns him not to tell anyone else about what they have done. The next day a reanimated Church returns to the house, a shell of what he was before; he stinks, moves sluggishly, and is vicious towards Louis. Jud explains that as a boy he himself revived his beloved pet dog in the Micmac ground, and that although the cat might be different, it will save Ellie the grief of losing her favorite pet.
Sometime later, the young Gage is killed by a truck along the same highway. The family is devastated, and Jud anticipates that Louis is considering burying his son in the Micmac ground, although Louis denies it. Jud believes that introducing Louis to the ritual ground aroused the malevolent forces present there, which caused Gage's death. 
Question: Who is a shell of what they once were?
Output (English): Church.