In Edith Wharton's 1903 novella Sanctuary and Ernest Hemingway's posthumously published short story “I Guess Everything Reminds You of Something,” both authors write about a parent worried about a child's tendency to plagiarize. In each case, the inherited propensity for immoral behavior stands in for the inherited bipolar disorder that affected both Wharton's husband, Teddy, and Hemingway himself. The authors implicitly evoke degeneration theory, an ugly offshoot of the pseudoscience of eugenics popular in early twentieth-century America, to explore the dangers of paternal inheritance. The negative eugenics widely accepted in America during the first half of the twentieth century would dictate that people with genetic mental illness should not be allowed to reproduce at all. Not surprisingly, the mother in Wharton's novella and the father in Hemingway's short story are each plagued by guilt over a son's immorality. In these critically neglected works of short fiction, a concerned parent broods over whether a child's hereditary propensities can be overcome by a loving upbringing and supportive environment. Both Wharton and Hemingway wrestled with bipolar disorder and its devastating symptoms in their own families and wrote stories in which they expressed personal and cultural anxieties about the illness's devastating impact.