Princess Eugenie has congratulated her sister Princess Beatrice on her pregnancy, saying she is looking forward to the addition of “another little one to the gang”.

Eugenie, who is mother to two boys, three-year-old August and one-year-old Ernest, shared a snapshot of her family with Beatrice’s at the beach from Christmas 2022.

Buckingham Palace issued a statement on Tuesday announcing Beatrice, 36, and husband Edo Mapelli Mozzi, 40, were expecting their second child together, with the baby due in early spring.

Eugenie’s photo shows her husband Jack Brooksbank wearing a Santa hat as he holds son Ernest as he splashes his boots in the water, while Mr Mapelli Mozzi prepares to help daughter Sienna.

The princess wrote on Instagram: “Congratulations Beabea.. So looking forward to more on this journey of motherhood together. And adding another little one to the gang.

“I couldn’t find a single group shot of us, so this one from Christmas 2022 will have to do.”

Standing close by are Beatrice and a then-pregnant Eugenie, both wearing bobble hats, winter coats and wellies.

The royal baby will be a little brother or sister for three-year-old Sienna, and Mr Mapelli Mozzi’s son and Beatrice’s stepson, eight-year-old Wolfie.

Beatrice’s mother Sarah, Duchess of York – the ex-wife of the Duke of York – has also expressed her joy, writing on social media: “A very proud GiGi/Mum today. Such an incredible blessing and an embrace to my heart.

“Wolfie, August, Ernie and Sienna will be over the moon to have the fifth member of the five aside!”

The happy news comes during one of the royal family’s most personally challenging years, with the duchess, the King and the Princess of Wales all being diagnosed with cancer.

Sarah was treated for malignant melanoma skin cancer in January, just months after undergoing a mastectomy for breast cancer, but Beatrice said in May the duchess had been given the “all clear”.

Elizabeth, in honour of the late Queen, is now the new favourite at bookmakers Coral in the royal baby name betting, with odds of 2-1, with Victoria at 3-1, Arthur at 5-1 and Oliver and Mary at 6-1.