Speak in the present
Too often “Don’t do that” is accompanied by a dire prediction, “or you’ll poke your eye out.” “You can’t go outside to play because a stranger might snatch you.” This is the way parents convey their own fears to their children, and those fears pass on generation to generation.
Such fears are based on statistically insignificant occurrences magnified by a national press trying to fill each news cycle with stories spun to exert maximum pathos, concern or exhilaration. Such stories are breathless, yet breadthless. They stir a prurient interest in the negative experience of others, reinforcing a negative viewpoint of the world. Such stories appear to be selected more on their proximity to gossip than newsworthiness.
Gossip is mostly speculation; using examples from the past to guess what might occur in the future; which squeezes out time for living in the present. Speaking in the present can inform children about the past in order to plan for the future, but the emphasis is on the now.