"Faith in humanity," yes. However, there is a little matter of physics.
It takes a train more than a mile to stop once it begins to apply the brakes. Even if the engineer has very good eyes, then, he may just kill your 4-year-old child simply because the train won't stop in time to do otherwise.
Well, 4-year-olds are nimble. Not like you tied her to the track, I hope?