Sarah Ferguson arrives at the UK premiere of “Marlowe”; Princess Eugenie Welcomes Second Baby

Jo Hale/WireImage; Princess Eugenie Instagram

Sarah Fergusonis loving life as a grandmother toPrincess Eugenie’s newborn son!

The Duchess of York, who is popularly known as Fergie, sent the well-wisher a double-sided note that featuredErnest’s pictureon one side and a handwritten message on the other.

“Ernest George Ronnie,” Fergie wrote with a heart. “Such a total joy to our hearts… our new little lion cub.” The note was signed, “Love Sarah.”

The sweet sentiment matched the card it was written on, which featured an illustrated border of tropical branches and animals including a monkey, birds and a lion cub.

The picture of Ernest was the same snap Princess Eugenie, 33, shared onInstagramto announce the birth of her son and the inspiration behind his name.

“Jack and I wanted to share the news that we had our little boy, Ernest George Ronnie Brooksbank on 30th May 2023 at 8.49 weighing 7.1lbs,” the royal wrote on June 5. “He is named after his great great great Grandfather George, his Grandpa George and my Grandpa Ronald. Augie is loving being a big brother already.”

Princess Eugenie Welcomes Second Baby with Husband Jack Brooksbank

Princess Eugenie/instagram

Ernest’s middle names honorQueen Elizabeth’s grandfather King George V, Jack’s late fatherGeorgeand Eugenie’s maternal grandfather Ronald. The infant arrived as 13th in theline of successionto the British throne, immediately following big brother August.

Princess Eugenie Welcomes Second Baby with Husband Jack Brooksbank

Ernest is the first ofQueen Elizabeth’s great-grandchildren to be born following her death in September and the third grandchild ofPrince AndrewandSarah Ferguson.

The Duke and Duchess of York,who divorced in 1996after a decade of marriage but remain close today, are already grandparents to August andPrincess Beatrice’s 1-year-old daughterSienna Elizabeth, whom she shares with husbandEdoardo Mapelli Mozzi. Edo is also dad to son Christopher Woolf, known as “Wolfie,” whom he shares with ex-girlfriend Dara Huang.

“So my grandchildren had the most incredible weekend. I was very lucky, I had everybody in. I had Edo and Beatrice and Jack and Eugenie and August and new Ernest. Well, Ernie,” she told her co-host, Sarah Thomson.

“Yeah, it’s Ernie,” Fergie confirmed.

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Princess Eugenie, Sarah Ferguson, Duchess of York and Princess Beatrice at an NYC event in 2015.Janette Pellegrini/Getty

Princess Eugenie, Sarah Ferguson, Duchess of York, Princess Beatrice attend Annual Charity Day hosted by Cantor Fitzgerald and BGC at BGC Partners, INC on September 11, 2015 in New York City

Janette Pellegrini/Getty

The Duchess of York previously toldPEOPLEthat she and her daughters call themselves “the Tripod” and she cherished everything about being a grandmother.

“One, I’m really proud of my girls. Two, I have very good grandchildren,” the author ofA Most Intriguing Ladysaid in the spring.

“They just follow me around like Peter Pan. I’m ‘Super Gran Pan.’ Whenever they see me, they laugh. They think I’m very funny,” she added.

While Princess Eugenie is now a mom of two under age 2, she’s taking time to care for her mother after surgery. On June 26, a representative for the Duchess of York confirmed to PEOPLE that she wasrecently diagnosedwith an early form of breast cancer and had a successful mastectomy.

As Fergie rests at home at Royal Lodge, her daughters Eugenie and Beatrice have been popping in to see her, a source close to Sarahtells PEOPLE.

“Her daughters have been there a lot, they have been very supportive,” the source says.

Princess Beatrice, Sarah Ferguson, Duchess of York and Princess Eugenie.David M Benett/Dave Benett/Getty Images

Princess Beatrice of York, Sarah Ferguson, Duchess of York and Princess Eugenie of York attend the launch of The Ned

source: people.com