By Blood Possessed Mass market paperbound - 2001

From the publisher

Pat Montella is summoned from her dreary office job in suburban Pennsylvania by an unusual request from a stranger: Ninety-one-year-old Magnolia Shelby wants to bequeath to Pat in her will her house and acreage in rural Virginia, and the only condition is that Pat visit during the first week of May to learn what this is all about.
What she finds is Bell Run, a Civil-War-era estate and battle ground inhabited by the enigmatic Miss Maggie, a retired history teacher with a passion for the Civil War. And that's not all, for just as Pat begins to get the lay of the land, she finds herself noticing curiously out-of-date details, like the vibrations of bullets hitting old wood, or the smell of campfire coffee and roast pork, or the faraway hissing of a steam engine. Before too long, she has to admit that what she's hearing, seeing, and smelling are the details of an era long past, the sights and sounds of 1863. Pat soon begins to see enough about these long-ago events to put some of the facts together. But then she learns something extraordinary, and how this knowledge affects Pat and Maggie in 1990s Virginia stirs up some very modern, very real danger.