Donald Barnhouse was the pastor of Philadelphia's Tenth Presbyterian Church when his wife died and left him with young daughters to raise alone. He conducted his own wife's funeral. While driving to that funeral, he realized that he had to say something to his girls to somehow put in perspective for them something with which he himself was already struggling.

They stopped at a traffic light. It was a bright day, and the sun was streaming into the car. A truck pulled up next to them and its shadow darkened the inside of the car. Barnhouse turned to his daughters and asked, "Would you rather be hit by the shadow or by the truck?"

One of them responded, "Oh, Daddy, that's a silly question! The shadow can't hurt you. I'd rather be hit by a shadow than by a truck."

Then he explained that their mother had died and that it was as if she'd been hit by a shadow. It was as if Jesus had stepped in the way in her place, and it was He who'd been hit by the truck. He then quoted the familiar words of [Psalm 23:4, "Even though I walk through the valley of the shadow of death, I will fear no evil, for you are with me."
http://www.christianitytoday.com/moi/2001/001/jan/3.3.html