" The light bounced off the water and shimmered against the buildings on the other side of the river. Joseph walked, listening to the sound of what was beneath his feet, and soon he noticed he was alone. He turned and saw Frankie had stopped beside Albert and filled her jacket pockets. Looking at the two of them, Joseph wondered for a moment if Leo had ever come down here to go mudlarking, his red hair shining in the sun. the vision seemed so vivid, but then Joseph remembered that Leo wasn't real, and the boy dissolved like smoke into the winter sky. "

― Brian Selznick , The Marvels