Who are the parents of Viva Katherine Wainwright Cohen?

Viva Katherine Wainwright Cohen (d.o.b. 2/2/11) is the heir to folk music royalty. As the granddaughter of Loudon Wainwright III, Kate McGarrigle, and Leonard Cohen, she starts off life with songs -- and poetry -- in her blood. (By the way, I'm old enough to think of Rufus as the son of Loudon, rather than Loudon as the father of Rufus. As a folk music DJ in the early 1970's, I came of age