Patty Wirtz was the voice of B.J. on the popular children's show, "Barney and Friends," which aired from April 1992 until 2009. The show was educational and popular, featuring dinosaurs (in costume) and visiting celebrities, who participated in storytime. B.J. was a yellow Protoceratops, who wore red sneakers and a matching baseball cap, that made his first appearance on September 27, 1993. He is the older brother of Baby Bop, who is Barney's best friend. "B.J.'s Song" was his special theme song, which played when he made an appearance on the show. While Wirtz provided the voice of B.J., she was not the person in the costume. Wirtz's acting career has consisted of her role behind the scenes on "Barney and Friends," both the series and the movies. She has not had any roles since the television show went on hiatus in 2009. It is unknown how Wirtz began her career or any other roles that she has portrayed.