Sarah Harding, from the UK pop group Girls Aloud, has died at 39. Last year, she revealed that she had been diagnosed with breast cancer. Her death was announced in an Instagram post from Harding’s mother Marie.

“It’s with deep heartbreak that today I’m sharing the news that my beautiful daughter Sarah has sadly passed away,” she wrote in the message. “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.”

In 2002, Harding auditioned for the reality show Popstars: The Rivals, which resulted in the formation of Girls Aloud. Harding — alongside Nadine Coyle, Nicola Roberts, Cheryl Tweedy, and Kimberley Walsh — went on to have four UK chart-topping singles and 21 Top 10 hits with the group. Girls Aloud put out five full-length albums between 2003 and 2008. They went on hiatus in 2009 and, after a brief reunion for the group’s 10th anniversary in 2012, they officially disbanded in 2013.

Harding then went on to pursue a career in acting, appearing in some films and television shows. She also appeared on Celebrity Big Brother and put out some solo material, including 2015’s Threads EP.

“It meant the world to Sarah and it gave her great strength and comfort to know she was loved,” Harding’s mother wrote in her Instagram post. “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.”