* To highlight the divide between North and South. The Civil War was a defining event in American history, and the novel uses the experiences of the Creightons to show the different perspectives and struggles of families on both sides of the conflict. A Southern family member visiting the Creightons would create a direct contrast and highlight the clashing ideals of the North and South.
* To explore the complex relationship between families and the war. The war wasn't just a political conflict, it was a personal one that tore families apart. The author might use the visit of the Southern family member to explore the emotional complexities of the war and how it affected families on both sides.
* To provide a voice for the South. The novel primarily focuses on the experiences of the Creightons, who are from the North. By introducing a Southern family member, the author could provide a different perspective on the war and offer insights into the Southern way of life and their motivations.
* To show the impact of the war on individuals. Even though the Creightons are from the North, they are not immune to the war's impact. The visit of a Southern family member might force them to confront the realities of the war and its consequences on both sides.
* To create conflict and drama. A family member from the South visiting the Creightons would inevitably create tension and conflict, especially given the war's influence on relationships. This conflict could serve as a catalyst for character development and plot advancements.
Ultimately, the author's specific reason for introducing a Southern family member is open to interpretation. However, it is likely that the author used this device to explore the multifaceted nature of the Civil War and its impact on families, relationships, and individuals.