The arrival of a new royal baby is always a cause for celebration, but when Princess Beatrice recently announced the birth of her daughter, Athena Elizabeth Rose, she made headlines for an unexpected reason: her tiny weight. At just 4lbs 5oz, Athena is the lightest royal newborn in history. But Athena’s size is far from unique within the royal family. Over the years, royal babies have ranged from tiny miracles to healthy yet hefty bundles of joy. Here, we take a look at the lightest and smallest royal babies, from Athena’s delicate 4lbs 5oz to other royal infants who started their lives far from average weight.

Athena Elizabeth Rose – 4lbs 5oz

Princess Beatrice’s daughter Athena, born on January 22, 2025, is not only the lightest royal baby but also an immediate member of the royal family’s fascinating history. Born just last week, Athena’s arrival came with the joyful announcement that she had entered the world at 4lbs 5oz, which makes her the smallest royal baby by a significant margin. Despite her small size, Athena is already making waves in the royal lineup as she immediately became 11th in line to the British throne, pushing her aunt, Princess Eugenie, to 12th.

Her birth was celebrated by proud parents, Princess Beatrice and Edoardo Mapelli Mozzi. Edoardo, sharing the news on Instagram, gushed about Athena’s tiny yet perfect arrival. The couple expressed their deep gratitude to the exceptional staff at Chelsea and Westminster Hospital for their care during this special time. Athena’s grandmother, Sarah Ferguson, also shared her excitement in welcoming her newest granddaughter, declaring that Athena is already “so adored.”

While her arrival was joyous, Athena’s tiny frame stands in stark contrast to other royal babies, who have varied in size over the years.

Lady Louise Windsor – 4lbs 9oz

Lady Louise, daughter of Prince Edward and Sophie, Countess of Wessex, was born prematurely on November 8, 2003. Arriving four weeks ahead of schedule, Lady Louise weighed just 4lbs 9oz. Her birth was marred by complications, with her mother suffering significant blood loss due to internal bleeding, which led to an emergency caesarean. Lady Louise was rushed to St George’s Hospital for specialist care, and Sophie was kept at a nearby hospital for further treatment.

Despite the traumatic birth, Lady Louise has grown into a graceful and accomplished young woman, continuing the royal family’s tradition of overcoming adversity. Her small size at birth, however, still serves as a reminder of the early days of her life.

Prince Edward – 5lbs 7oz

Prince Edward, born on March 10, 1964, was the lightest of his siblings. Weighing only 5lbs 7oz at birth, he arrived at Buckingham Palace to a unique delivery story. Queen Elizabeth broke royal tradition by having Prince Philip join her in the delivery room—a moment that was celebrated as a symbol of the growing involvement of fathers in childbirth. Edward’s arrival was a moment of joy, and his relatively small birth weight has been remembered as part of the royal family’s diverse history of royal babies.

Princess Anne – 6lbs

Princess Anne, the second child of Queen Elizabeth II and Prince Philip, arrived at Clarence House on August 15, 1950, weighing 6lbs exactly. Her birth was not only historic for being one of the last to take place in a royal residence, but also for the fact that the Queen had to relocate due to wartime damage to Buckingham Palace. Princess Anne’s birth was celebrated with gun salutes, marking the arrival of the Queen’s only daughter, who would go on to play a pivotal role in royal life.

Queen Elizabeth II – 6lbs

Queen Elizabeth II herself had a birth weight of 6lbs. Born on April 21, 1926, in the heart of London, her birth took place at 17 Bruton Street, the home of her maternal grandparents. It was an event marked by custom, as the Home Secretary was present to ensure the legitimacy of the royal heir. Though not an unusually low weight, the Queen’s early days set the stage for her historic reign.

James, Earl of Wessex – 6lbs 2oz

Prince Edward and Sophie’s second child, James, Earl of Wessex, was born on December 17, 2007, weighing 6lbs 2oz. His birth was much calmer than that of his older sister, Lady Louise, and was hailed as a joyous occasion for the royal couple. Edward described James as “very cute and very cuddly,” and the family was overjoyed at the smooth arrival after the traumatic experience they had with Louise.

Sienna Elizabeth Mapelli Mozzi – 6lbs 2oz

Sienna Elizabeth Mapelli Mozzi, the first child of Princess Beatrice and Edoardo Mapelli Mozzi, was born on September 18, 2021. Weighing 6lbs 2oz, Sienna’s birth was a momentous occasion for the royal family, with Princess Eugenie (Beatrice’s sister) sharing heartfelt messages of love and congratulations. The birth of Sienna also marked the beginning of a new chapter for the family, as her parents looked forward to introducing her to her older brother, Christopher Woolf.

Princess Beatrice – 6lbs 12oz

Princess Beatrice, born on August 8, 1988, weighed 6lbs 12oz when she entered the world. Although she wasn’t the lightest royal baby, her birth was still met with excitement and joy. After Beatrice’s arrival, Buckingham Palace issued a brief statement confirming that both mother and daughter were well. Beatrice’s birth was a moment that cemented her place in royal history as the first daughter of Prince Andrew and Sarah Ferguson.

The Range of Royal Babies

While some royal babies, like Athena Elizabeth Rose, have shocked the world with their small sizes, others have defied expectations by being born at more average weights. From the regal halls of Buckingham Palace to the calm, intimate atmosphere of Chelsea and Westminster Hospital, the birth stories of royal babies tell us more than just their sizes—they reflect the evolving traditions and personal stories of the royal family. Whether tiny or robust, these babies are part of a larger narrative, a tale of new life and new beginnings.

Conclusion

In royal circles, the size of a baby at birth may seem like a small detail, but it speaks to the variety and unpredictability of royal life. From premature arrivals to unexpected complications, the royal family’s youngest members continue to surprise and delight us with their unique birth stories. Athena Elizabeth Rose’s arrival at just 4lbs 5oz serves as a reminder that no matter the size, each royal birth marks the beginning of an exciting new chapter in history.