The Shiloh Renewal — Joan Woodruff

Two teenage girls, sisters a year apart, are in a terrible auto accident near where they live, a few miles from the Civil War battlefield at Shiloh. The older is killed outright. The younger is badly brain-damaged. In a coma, she meets people who are dressed oddly, who speak English but not quite the English she speaks. Eventually she comes out of the coma, but continues to see and talk with these people whom the reader soon identifies as doctors, nurses, and soldiers- Northern and Southern- who are on their way to Shiloh to fight a great Civil War battle. The girl is befriending people of the last century who are soon to die. As fascinating as these occurrences are, they are associated with the girl's refusal to accept the death of her sister. Indeed, her doctors expect the girl herself to die of her own injuries. But she fools everybody, and by witnessing the deaths of her Civil War-era friends she is able to come to terms with the loss of her sister.