How I became a ghost

"Ten-year-old Isaac, now a ghost, continues with his people as they walk the Choctaw Trail of Tears headed to Indian Territory in what will one day become Oklahoma. There have been surprises aplenty on their trek, but now Isaac and his three Choctaw comrades learn they can time travel--making for an unexpected adventure. The foursome heads back in time to Washington, D.C., to bear witness for Choctaw Chief Pushmataha who has come to the nation's capital...