I have never had the misfortune to have someone killed by a vehicle I have been operating. I imagine it must feel pretty bad for the the person at the controls even if there is absolutely nothing they could have done to prevent the tragedy, as a train can take a mile or more to come to a stop even with full emergency braking. In this case, it might have been someone trying to hop on a moving train, who didn't make it, or perhaps even a suicide. In such cases there is absolutely nothing the train operator can do. I remember a young lady about 2 years ago that tried to hop on a moving train in Fort Collins, CO. She slipped and fell, her legs went onto the rails and were amputated when the freight car wheel ran her over. The engineer and conductor operating the train in this case had no way to know or see what was happening dozens of cars behind the lead locomotive. People's stupidity is not the fault of the railroads or their employees operating the trains. I am sure your union sister can take some comfort in knowing this, but I am also sure it only helps a little.