Fwirl was an orphaned squirrel who lived outside of Redwall Abbey for many seasons until Cregga offered her residence at the Abbey. Foxes had supposedly killed her parents when she had been a child. Fwirl had large eyes, white teeth and was an excellent climber. She wore a short soft green tunic with a belt. Fwirl helped to solve the riddle of Abbess Songbreeze and she won the Wall Race with Gundil. She was wounded by an arrow shot from Vallug Bowbeast, but recovered. Later on, she married Broggle and was the mother of Sister Rosabel.