“She has been in not great health for several years now, you may be aware that dementia struck her about three years ago and she’s been getting progressively worse.”
Taking to her official Facebook page, Helen's children, Traci Donat and Jordan Sommers, confirmed her death in a statement on Wednesday morning.
"It is with deep sadness that we announce the passing of our beloved mother, Helen Reddy, on the afternoon of September 29th 2020 in Los Angeles," they wrote.
"She was a wonderful Mother, Grandmother and a truly formidable woman. Our hearts are broken. But we take comfort in the knowledge that her voice will live on forever."
Jordan also shared a sweet snap of his mother on Instagram, along with several purple hearts.
Helen, whose trailblazing life was the subject of a recent bio-pic I Am Woman, was best-known for the song of the same name, which turned her into a feminist icon.
After receiving a Grammy for the song in 1973, she went on to star in her own weekly prime-time variety show on TV, before branching into acting on screen and stage.
Regarded by many as the queen of pop in the '70s, Helen also released many other hits including, One Way Ticket, I Believe in Music, and I Don't Know How to Love Him.
Helen's career began in Melbourne, Victoria, where she sang on radio and television from age four, before later winning a talent contest on TV show Bandstand in 1966.
As part of her prize, Helen won a ticket to New York City to undertake a record audition, but after just missing out, she relocated to Los Angeles, where she eventually found success.