Strangers hurt you with fists. Family hurts you with memories. Complex characters know exactly which button to push because they watched you install it. They know about the failed business venture, the affair you had in college, or the time you wet the bed until you were twelve. In a great family storyline, a single line—"You always were Dad’s favorite"—carries the destructive force of a wrecking ball because it references thirty years of resentment.
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