Who is Lieutenant William Lawford from Sharpe's Tiger and what is their importance?

Lawford accompanies Sharpe on the mission to free McCandless. Lawford comes from a wealthy family and started his army career as an officer. He has none of the street-smarts of Sharpe and would be quickly killed if not for Sharpe's advice. This means that during the mission, Lawford must follow Sharpe's orders, which greatly annoys Lawford. Nevertheless, Sharpe earns his respect while in Seringapatam.