A seat for a transport vehicle includes a seat surface, an armrest, and a child armrest. The child armrest is configured to adopt an adult position and a child position. In the adult position the child armrest is arranged in a stowed position in which the child armrest is incorporated in a contour of the armrest. In the child position the child armrest is arranged in a use position in which the child armrest has a reduced spacing from the seat surface in the vertical direction and a reduced spacing from an opposing armrest in the horizontal direction.