Another inspiration for the book, after meeting the veterans and seeing Billy with Hebe the horse, was an old oil painting that Morpurgo's wife Clare had been left: "It was a very frightening and alarming painting, not the sort you'd want to hang on a wall. It showed horses during the First World War charging into barbed wire fences. It haunted me." The painting was by F. W. Reed and was dated 1917, and showed a British cavalry charge on German lines, with horses entangled in barbed wire. Morpurgo wrote a fictionalised version of this painting in his "Author's Note" at the start of the book. In his version, the painting shows a red bay with a white cross on his forehead, and the painting bears the legend: "Joey. Painted by Captain James Nicholls, autumn 1914.":)