Princess Eugenie has congratulated her "dear cousins" the Duke and Duchess of Sussex on the birth of their daughter.

Princess Eugenie

Princess Eugenie

The 31-year-old royal - who welcomed her son August into the world on February 9th - took to her Instagram Stories to share a black and white picture of Prince Harry, 36, and Meghan, the Duchess of Sussex, following the birth of their second child, Lilibet Diana Mountbatten-Windsor.

Underneath the photo, she wrote: "Congratulations dear cousins.. we couldn't be happier for you all (sic)"

Eugenie - who shares son August with her husband Jack Brooksbank - also posted three heart emojis before the caption, and another hat-trick of hearts afterwards.

Meghan, 39, gave birth to Lilibet on Friday (04.06.21) at the Santa Barbara Cottage Hospital in California.

The couple - who have two-year-old son Archie - said in a statement: "It is with great joy that Prince Harry and Meghan, The Duke and Duchess of Sussex, welcome their daughter, Lilibet 'Lili' Diana Mountbatten-Windsor, to the world.

"Lili was born on Friday, June 4 at 11:40 a.m. in the trusted care of the doctors and staff at Santa Barbara Cottage Hospital. Both mother and child are healthy and well, and settling in at home."

Later in the day, Buckingham Palace revealed Queen Elizabeth - who Lilibet was named after - Prince Charles; Camilla, the Duchess of Cornwall; and The Duke and Duchess of Cambridge were all "delighted" to hear of the pair's news.

A spokesperson said: "The queen, the Prince of Wales and the Duchess of Cornwall, and the Duke and Duchess of Cambridge have been informed and are delighted with the news of the birth of a daughter for the Duke and Duchess of Sussex."

Meghan's estranged father Thomas Markle has also said he is "very pleased".

He said: "I'm very pleased that my daughter and my new granddaughter had a successful delivery. I wish them all my love and the best of luck."