Loudon Wainwright III
Loudon Snowden Wainwright III (born September 5, 1946) is a Grammy Award-winning American songwriter, folk singer, humorist, and actor. He is the father of musicians Rufus Wainwright, Martha Wainwright and Lucy Wainwright Roche, brother of Sloan Wainwright, and the former husband of the late folk singer Kate McGarrigle.
source: Wikipedia