Kate, the Princess of Wales, apologized Monday for an edited family photo released by the palace.
News agencies withdrew the photo because of concerns it had been manipulated. People noted inconsistencies with clothing and body parts.
Some speculated that it was AI-generated, while others said it looked like it was a real photo that had been edited in Photoshop.
In a post on social media, the Princess of Wales wrote, "like many amateur photographers, I do occasionally experiment with editing."
"I wanted to express my apologies for any confusion the family photograph we shared yesterday caused," the post said. 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."
Kensington Palace released the photo for Mother's Day, which was celebrated on Sunday in Britain.
It was the first official photo of Kate Middleton since she underwent planned abdominal surgery nearly two months ago. She spent 13 nights at a London hospital following the surgery.
Few details about her condition have been released since, which has led to significant speculation about her health.
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.
Some royal fans have been spreading rumors about her for weeks.