Maria Gilhooley (née Knight), who records under the name Marry Waterson, is a singer, songwriter and visual artist. A member of the Waterson-Knight-Carthy family musical dynasty, Waterson is described as having "thrived on communal music making while developing highly original and distinctly English performance styles of [her] own."
Waterson is the daughter of Lal Waterson and George Knight and was born in the city of Hull, East Riding of Yorkshire. She made her recording debut as a guest on the album A True Hearted Girl by Lal and Norma Waterson in 1977. In 1988 she formed an occasional singing partnership with her mother Lal, aunt Norma and cousin Eliza Carthy under the name The Waterdaughters. She has since been a guest performer on numerous Watersons and Waterson–Carthy recordings and has often performed live with her family at festivals and special performances.
On 12 May 2007, Waterson appeared with the Waterson family at a special concert at the Royal Albert Hall entitled A Mighty River of Song, and on 25 October 2007, she appeared at the BBC Radio 2 Electric Proms concert Once in a Blue Moon: A Tribute to Lal Waterson at Cecil Sharp House in London.
In 2007, Waterson replaced Eliza Carthy in Blue Murder, and made her concert debut with that group on 23 November at the Met Theatre in Bury, Greater Manchester.
In January 2010, Waterson performed at the Sydney Opera House in a line-up of rock, punk, pop and folk musicians under the musical direction of Hal Willner as part of his Rogue's Gallery project.