Sarah Ferguson is "excited" to be a "granny"

Speaking on the latest installment of her children's YouTube series 'Story Time with Fergie & Friends', Sarah exclaimed as she waved a magic wand: "Hello! Magic dust is in the air.

"Very exciting times — and I'm a granny!"

To mark the occasion, the duchess read a book called 'Baby on the Way', but first had to put on her "granny hat" and "reading granny glasses".

Eugenie and Jack have yet to share their baby's name publicly but following the official announcement of their son's birth last week, the princess

posted the first picture of her little one's hands on her Instagram account, which she captioned with a string of blue love hearts.

Meanwhile, Sarah previously predicted her daughter will prove to be a "great mother" because she is "empathetic, very strong and determined".

She recently said: "Having not had my own mother around, I’ve always been determined to be a very present mother with my children, and I know Eugenie will be the same with hers.

"She is incredibly empathetic and will be a great mother. She is a very strong and determined person, always looking for the truth in all she does.

"Her work for the Anti-Slavery Collective is a commitment she steadfastly campaigns for, to give everyone the chance to have a voice ...

"Jack and Eugenie are certainly looking forward to sharing the new baby with the whole family. I have always been so close to my girls and it is such a joy to see them embarking on this next phase of their lives. We call ourselves the tripod and it’s a real honour to see them grow."