When individuals cannot resolve a disagreement in a single episode, the argument is likely to reoccur over time resulting in a serial argument. Prior research on serial arguing has shown that engaging in hostile communication during episodes and taking a resigned stance after episodes is detrimental to one’s physical health. This study investigates the mechanisms by which hostile communication and taking a resigned stance lead to negative outcomes in a sample of emerging adults. Mutual hostility is related to physical and mental health symptoms and this relationship is mediated by the degree to which the participants feel hyperaroused. Taking a resigned stance toward a serial argument with one’s parent is related to health symptoms and this relationship is mediated by the participants’ rumination after argumentative episodes.