Sarah Ferguson told the Daily Mail she had signed a deal with a major US movie company to work on big-screen versions of the five books, which are aimed at four-to-eight-year-olds and centre on a red-headed girl and her various adventures. The deal also includes the 49-year-old's most recent effort, Tea for Ruby, a book for under-fours about an accident-prone red-haired child who is invited to meet the Queen.

"The films will run as a series. I cannot yet tell you the name of the film company," Ferguson said, adding, "I cannot tell you how exciting that is for me. America has been so good to me. "I failed in Britain, and when I gave it a go in America I was ready to fail there, too - but they have really embraced me," she said.