Denise Michelle Crosby (born November 24, 1957) is an American actress best known for portraying Security Chief Tasha Yar in Season One of Star Trek: The Next Generation as well as Yar’s own daughter, the half-Romulan Commander Sela, in subsequent seasons. She is also known for her numerous film and television roles and for starring in and producing the film Trekkies. She is the paternal granddaughter of entertainer Bing Crosby.