The light shines on Laura even when she is not part of the dialogue onstage, to emphasize to viewers that she is central to the action. In fact the whole play revolves around the fragile, disabled, socially inept Laura. She is the glue that holds this dysfunctional family together. She is the focus of her mother Amanda's attempts to marry her off. She is also the reason Tom continues to work in the warehouse in order to support her and Amanda, despite the bad relationship between mother and son.