I know every story element should have a purpose, and readers would expect a weapon introduced to be used as some point. But, can you create a false foreshadow from a detail? For example, in my book, two sisters (children) lose their father when he's hit by a car. In turn, they are anxious about crossing the street. Now, will readers assume the girls will also get hit by a car at some point or at least a near miss? That's not part of my story. It seems like adding a character's fear in a story usually means that person is going to face it. But, in this instance, the story is not about them overcoming their fears, but the effects from their father's death.