In an exclusive quote obtained by HELLO!, the new grandmother said: "I am so excited and thrilled to have become a grandmother. August Philip Hawke Brooksbank, a wonderful grandson and he brings such joy, smiles and love to all our family.
She continued: "Jack and Eugenie are and will be superbly caring and wonderful parents."
WATCH: Princess Eugenie reveals royal baby name
The royal also took to Instagram to reiterate her joy at her grandson's arrival, writing: "As Grandparents, The Duke and I are thrilled and blessed at the arrival of our grandson August Philip Hawke Brooksbank.
"He is a beautiful blessing and a bringer of such love and joy to all our Family. I am so proud of Jack and Eugenie, they are and will be wonderful parents."
The Duchess of York says she is "thrilled to have become a grandmother"
Eugenie and her husband Jack Brooksbank welcomed their first child on February 9 2021, and confirmed his name in an Instagram post on Saturday, the day after the Duke of York's 61st birthday.
Alongside a gorgeous photo of her and Jack holding the newborn, she wrote: "We wanted to introduce you to August Philip Hawke Brooksbank. Thank you for so many wonderful messages. Our hearts are full of love for this little human, words can't express. We are excited to be able to share these photos with you."
She added that the photo had been taken by their "wonderful midwife" at the Portland Hospital. "Thank you to the wonderful essential workers including our midwife who came to discharge our boy."
Eugenie and Jack left hospital with their newborn son last week
The couple are currently residing at Prince Harry and Meghan's Windsor home, Frogmore Cottage, close to Prince Andrew and Sarah's abode, Royal Lodge.
Eugenie shared the first photo of her son on Instagram on the day of his birth - an adorable black and white image of the proud parents holding their baby's tiny fingers.
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