Sarah Ferguson is referring to the endearing letter she composed for King Charles III.
After taking her granddaughter Sienna to Windsor Great Park, the Duchess of York expressed her appreciation for His Majesty's environmental initiatives.
"You can't imagine, Sienna had the best day ever," the Duchess told Teatalks co-host Sarah Thomson. It is the best adventure playground she has ever visited."
"I thought that was just so sweet — they say out of the mouths of babies, well out of the mouths of young people — enjoying the vision that the King had all those years ago and seeing it come to fruition," Fergie remarked.
"It's simply extremely unique... The small zip line for two-year-olds was apparently her favourite feature – cute!"
Fergie goes on to explain how she showed the images to King Charles.
"I had some pictures made into cards and wrote to the King, saying your vision was the greatest success ever and Sienna's favourite thing ever."
"I just love the idea that a two-year-old has gone out into the world and said 'you are on the right track'... all his climate change talk, all his vision, all his wishes, and now it's all coming true," she added.
"People are starting to realise what an incredible force he's been in fighting with the force of nature, fighting for nature," Sarah writes.