Olivia Newton-John, the Grammy-winning singer who led a successful decades-long career, passed away on Monday at her southern California ranch at age 73. "Olivia has been a symbol of triumphs and hope for over 30 years sharing her journey with breast cancer," her husband John Easterling wrote on Instagram. "We ask that everyone please respect the family’s privacy during this very difficult time." The star, a longtime resident of Australia whose sales topped 100 million albums, was among the world’s most popular entertainers from 1973 to 1983.