Based on nearly four years of research, including original archival material, he fills an important gap in the military history of World War I. A Grateful Heart is a detailed account of the 103rd Field Hospital Company, 26th (Yankee) Division in World War I.

Shay looks at the crucial yet unheralded role played by support troops in World War I, in particular those in the medical branch. The unarmed men of the 103rd Field Hospital Company, 26th (Yankee) Division spent a year and a half in France performing their duty bravely under arduous conditions. The experiences of the men of the 103rd Field Hospital were undoubtedly shared by any member of a frontline field hospital. Based on nearly four years of research, including original archival material, he fills an important gap in the military history of World War I. A Grateful Heart is a detailed account of the 103rd Field Hospital Company, 26th (Yankee) Division in World War I. All aspects of the company are examined. The book is more than a chronological narrative and it places the unit in the context of the larger role of the 26th Division. It features original maps and passenger lists showing the members of the unit who sailed to France in 1917 and who returned in 1919.