Princess Beatrice's daughter Sienna and Eugenie's sons August and Ernest love playing with these classic toys

Sarah, Duchess of York has opened up about being a hands-on grandmother, revealing the toys that her three grandchildren love to play with.

The Duchess' eldest daughter Princess Beatrice , who is expecting her second child next spring , has three-year-old Sienna, while Princess Eugenie is mum to sons, August , three, and one-year-old Ernest.

Describing what it's like to be a grandmother as she appeared on ITV's This Morning on Thursday, Sarah, 64, said: "It is one of the most precious, joyful, exciting moments because you're so proud of your own children, and they've done such a good job."

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She continued: "But then these are little naughties again, but you can play again. And since I am clearly only a 3-year-old, I am actually loving making Barbie houses again. I forgot…"

And speaking about the difference in being grandmother to boys August and Ernest, the Duchess added: "Now I have to play trains. Boys are different, and I've got to know how to play with the train and not to do it wrong, and you know I've got to get it right, so it's really the most extraordinary thing to be a grandmother."

© Instagram / @sarahferguson15

Sarah has previously spoken about having a "fairy picnic" with Sienna for Beatrice's birthday last year and how August is teaching her how to "play trains and diggers".

The children are regular visitors at Royal Lodge in Windsor – Sarah's home she shares with her ex-husband, Prince Andrew.

© Instagram

Hours after Buckingham Palace shared Beatrice's pregnancy news, the Duchess took to her own personal Instagram to post some sweet family snaps and to express her joy at being a grandmother for the fourth time.

"Darling Beatrice, words can't quite express the joy and excitement I feel as you and Edo prepare to welcome another precious addition to your beautiful family," Sarah wrote in a heartfelt message. "Becoming a granny again fills my heart with so much happiness and gratitude.

© Ken McKay/ITV/Shutterstock

"Watching you grow as a mother has been one of the greatest privileges of my life, and now to see your family blossom further is an absolute blessing. Our family is growing, and so too is the love that surrounds us. I cannot wait to meet this little one and to share in all the wonderful memories we will make together. All my love."

The Duchess has just released her latest children's book, Flora and Fern: Wonder in the Woods .

LISTEN: Why King Charles was the one to announce Beatrice's baby news

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