At the end of episode four, Kate wears this rose-embroidered dress, which seems to blend in with the rest of the ballroom and the guests who inhabit it. As she dances with Anthony, promising Edwina she will encourage him to propose to her younger sister, Kate's melding into the colour scheme, which allows us to visualize her in Anthony's arms as a romantic partner. The dress, in a sense, embodies what "could be" between them.