She was born Carmen R. Attkisson on December 23, 1896 in Parkersburg, West Virginia. Her father, Richard Attkisson, was a bookkeeper. Sybil was raised in Pittsburgh and attended Bellefield Public school. She later moved to New York City to become a dancer. In 1915 she was discovered by composer Gene Buck. He introduced her to Florenz Ziegfeld who cast her as a balloon girl in the The Midnight Frolic. The petite dancer quickly became an audience favorite. She would spend more than two years performing with the show. Sybil made her film debut in the 1918 drama A Romance of the Underworld. She also starred in the Century Grove Midnight Revue. During the Summer of 1919 she suffered a nervous breakdown and spent six weeks recovering at her mother's house in Pennsylvania.
She married film executive Maurice S. Revnes on September 8, 1919. The following year she was a featured performer in The Ziegfeld Follies. Then she had a small role in the 1921 film Experience (she was billed as Sibyl Carmen). She and her husband had two children - Carmen in 1921 and Richard in 1923. Sybil decided to quit show business and became a full-time wife and mother. When Maurice was offered a job with Pathe Studios in 1926 the family moved to Paris, France. Tragically on April 14, 1929 she died suddenly from a heart attack. Some sources claim she died from pneumonia. She was only thirty-two years old. Sybil was cremated and her ashes were returned to the United States.