Crewman Ethan Mathews was a Starfleet security crewman assigned to the USS Enterprise, under the command of Captain James T. Kirk, in the 2260s. In late 2265, Mathews attended Lieutenant Lee Kelso's memorial service that was held in the ship's chapel. He sat on the front-row and was accompanied by his colleague, Edward Rayburn, Lieutenant Stiles and Captain Kirk. (TOS - My Brother's Keeper novel: Constitution)