The British royal family on Sunday released the first new picture of Kate Middleton since she was hospitalized nearly two months ago for a planned abdominal surgery - following weeks of speculation about the Princess of Wales' health and whereabouts.

The photo, credited to Prince William, shows Kate, 42, sitting down while surrounded by her three children - Princess Charlotte and Princes George and Louis.

"Thank you for your kind wishes and continued support over the last two months," the photo was captioned on social media. "Wishing everyone a happy Mother's Day."

In the United Kingdom, Mother's Day is celebrated on the fourth Sunday of Lent, rather than the second Sunday in May, as in the U.S.

Social media speculation about Kate's whereabouts has grown increasingly common in recent weeks - with many questioning official statements regarding her health. On January 17, Kensington Palace shared that she was admitted to the hospital for a "planned abdominal surgery" and was expected to recover in the hospital for two weeks.

The princess - who had not been seen in public since Christmas - shared that she would not resume her official duties until Easter. At the same time, King Charles III shared that he was undergoing treatment for an unspecified form of cancer, while Prince William suddenly dropped out of a memorial service for his godfather.

As rumors spread across social media, the palace released an additional statement regarding their communication with the media.

"Kensington Palace made it clear in January the timelines of the princess' recovery and we'd only be providing significant updates," the palace said on February 29. "That guidance stands."