Skye was born Ione Skye Leitch in Hampstead, London, England, the daughter of folk singer-songwriter Donovan and model Enid Karl (née Stulberger). Her father is Scottish, and her mother was an American of Jewish descent who was raised in the Bronx, New York City. Her second name comes from the Isle of Skye. She is the younger sister of Camp Freddy singer Donovan Leitch. Skye's parents were separated at the time of her birth, and she was raised by her mother, having little to no contact with her father.