The singer, who performed with the “Love Machine” girl group from 2002 to 2013, revealed last year that she had been diagnosed with breast cancer, with the disease advancing to other parts of her body.
Her death was announced on Sunday with a post shared on Harding’s Instagram page by her mother Marie, who wrote that her daughter had died “peacefully” in the morning.
“It’s with deep heartbreak that today I’m sharing the news that my beautiful daughter Sarah has sadly passed away,” she wrote.
“Many of you will know of Sarah’s battle with cancer and that she fought so strongly from her diagnosis until her last day. She slipped away peacefully this morning. I’d like to thank everyone for their kind support over the past year. It meant the world to Sarah and it gave her great strength and comfort to know she was loved.”
Marie continued: “I know she won’t want to be remembered for her fight against this terrible disease – she was a bright shining star and I hope that’s how she can be remembered instead.”
Writing in her memoir Hear Me Out earlier this year, Harding revealed that she had undergone a mastectomy and intensive chemotherapy following her diagnosis.
While it initially “seemed like the chemo was working”, she wrote, the cancer spread further with a secondary tumour growing on either the base of her spine or her brain.
She also revealed that Christmas 2020 was “probably my last” and that she had nearly died of sepsis in hospital, having to be put into a coma for two weeks.
Rising to fame aged 21 on Popstars: The Rivals, Harding performed with Girls Aloud for 11 years, during which they earned 20 consecutive top 10 singles – four of which went to number one – and a Brit Award.
The band went their separate ways in 2013 after their final tour date together.
In 2017, she won Celebrity Big Brother and had also pursued a career in acting.
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