Task: Question Answering
Input (English): Passage: Sam Lawton is on his way to a company retreat with his colleagues. While their bus crosses the North Bay Bridge, Sam has a premonition that the bridge will collapse, killing everyone except his ex-girlfriend Molly Harper, whom he manages to get across the bridge safely. In a panic, he persuades several people to leave the bridge before it collapses, including Molly, his friends Nathan Sears and Peter Friedkin, Peter's girlfriend Candice Hooper, his boss Dennis Lapman, and his co-workers Olivia Castle and Isaac Palmer. FBI agent Jim Block doesn't believe that Sam is responsible for the bridge collapse, but promises to keep an eye on him. At the memorial service, coroner William Bludworth mysteriously tells the survivors that "Death doesn't like to be cheated," and warns them to be careful. However, they ignore his warning and leave, believing this to be nonsense.
Later, Candice goes to the gym to practice with Peter, but a chain reaction causes her to fly off the uneven bars, and she snaps her spine, leaving Peter devastated. The next day, Isaac is killed at a Chinese spa when his head is crushed by a falling Buddha statue during an acupuncture session. Bludworth, who has been present for both deaths, tells the remaining survivors that if they wish to cheat Death, they must kill someone who was never meant to die on the bridge, and thereby claim their remaining lifespan. On the same day, Olivia goes to an eye surgery clinic to treat her myopic vision. While the doctor is away looking for files, the laser malfunctions, searing her eye and hand. She manages to free herself just as Sam and Molly arrive to save her, but trips and falls out of the window onto a car below. Later, Sam learns that the survivors are dying in the order they were meant to die on the bridge, and realize that Nathan is next. 
Question: What is the relationship of the person whose head is crushed by a falling Buddha statue to Sam?
Output (English): co-worker.