Jamaican singer-songwriter known for her 1964 cover of The Cadillacs' song "My Boy Lollipop," and popularized the "bluebeat" style.
She and Roy Panton recorded as Roy and Millie when she was a teenager.
Her success with "My Boy Lollipop" was significant in that it was the first major hit for Island Records.
Her father was a sugar plantation overseer. She gave birth to a daughter.
She briefly dated British pop star Peter Asher.