A childhood belief about history

I don't seem to do a good job explaining things in an understandable fashion to small children. When my first child at the age of 4, watched Jerrassic Park with his father (while I was not present, obviously) and was quite shaken up by it, I tried to explain "extinct," while silently cursing my ex-husband for having been such a nimrod to let him watch it and leave me to deal with the trauma. After many failed attempts, I broke out the paleoentology book showing a Mammoth skeleton and explained that scientists dug up the bones from the ground and put them back together and from there they GUESS how the animal looked. This discussion led into how movie makers created animatronic dinosaurs for the movie and they didn't use real dinosaurs.
At bed time every night my son would run down his usual list of fears, seeking reassurance from me about each by stating, for example, "No thunder?" I would assure him who slept like a log, "no thunder." But I noticed, his list now included, "No dinosaurs in our yard?" I wasn't sure what he was afraid of but assumed none of my explanations had made any sense to him what-so-ever and just assured him, "No dinosaurs in our yard."

Years later, my son found a drawing I had done of a window with a gigantic dinosaur eye looking in at you, the viewer. He asked me what it was about. I told him about his "no dinosaurs in our yard," fear. He laughed and said that my attempts to explain paleoentology and animatronics to him, had him believing that dinosaurs were buried all over, everywhere, including our yard and could come up out of the ground at any moment in that T-Rex skeleton pose and materialize into the kind of dinosaurs Steven Spielburg caught and trained for his movie.

Go figure...