Sarah Ferguson has praised Princess Beatrice and Princess Eugenie's children as "inspiring."
The Duchess of York is set to attend Global Citizen NOW in Melbourne, Australia from March 4 to 6, where she plans to engage with young individuals to address the climate crisis.
Sarah, 64, the former wife of Prince Andrew, expressed how her four grandchildren - Wolfie, Sienna, August, and Ernest - serve as her source of inspiration.
Writing on Instagram, she said: "Ilook forward to listening to [young leaders], learning from them, and contributing whatever voice I have to speak up for the future of our planet.
"My parents always highlighted the need to champion the quiet voice of Mother Nature, and now even more so since becoming a grandmother I’ve become acutely aware of my responsibility, and that of my generation, to do everything we can to improve the state of the world we are leaving for our grandchildren."
Hugh Jackman and Charlie Puth will be present at the Global Citizen NOW action summit, of which Sarah is a co-chair.
This comes as the duchess recently urged people not to skip their health check-ups, warning that "days could make the difference between life and death" as she marked Cancer Prevention Action Week.
Sarah was diagnosed with malignant melanoma, a form of skin cancer, in January. This came less than a year after facing breast cancer.
Fergie said her diagnosis was a shock but she was "in the best hands and feeling positive".
The duchess travelled to the US earlier this month to take part in several charity events.
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