Kensington Palace released the first official photo of Princess Kate on social media on Sunday, nearly two months after her abdominal surgery, during which she has stayed out of the public eye.

The 42-year-old princess, whose husband Prince William is heir to the British throne, has been recovering mainly at their home in Windsor, west of London, since leaving hospital on January 29.

Princess Catherine and her children. Photo taken by Prince William.

The photo shows the Princess of Wales sitting on a garden chair, dressed in jeans, a sweater and a dark jacket, smiling, surrounded by her three laughing children, George, Charlotte and Louis.

"Thank you for your kind wishes and continued support over the last two months," a message accompanying the photo that was said on X said.

"Wishing everyone a Happy Mother's Day," said the message, which was signed "C" for Catherine.

In a statement the palace clarified that the photo was taken "in Windsor earlier this week" by Kate's husband, Prince William.

The family photograph is the first official image of Kate released by the royal family since her hospitalisation on January 16 for an abdominal surgery.

Her last public appearance was at the royal family's Christmas mass at Sandringham.

Photos published by TMZ earlier in March showed Kate wearing sunglasses while being driven in a car, with the celebrity news site saying they were taken Monday near Windsor Castle.

UK media outlets including the Daily Mail and The Sun have chosen not to publish the photos.

The sighting came after a flurry of conspiracy theories on social media over the famously hard-working and dutiful princess's absence from the spotlight.

The speculation came despite Kensington Palace clearly saying at the time of her surgery that she would be "unlikely to return to public duties until after Easter".

It also said the surgery was not related to cancer.

Kate's hospitalisation came almost simultaneously with the announcement that William's father, King Charles, had been admitted for surgery for a benign prostate condition and subsequently diagnosed with an unrelated cancer.

The king, 75, withdrew from public duties during his treatment, though he attended church services and held his weekly audience with the prime minister.

The princess, widely known as Kate, is one of the most popular members of the royal family.

She and William have taken on more royal duties since his younger brother Prince Harry and his wife Meghan left for the United States in 2020, and the king's brother Prince Andrew stepped back because of his friendship with the convicted sex offender Jeffrey Epstein.