Princess Kate left Windsor Castle alongside Prince William as she headed to a private appointment.
This was the first time the mother-of-three had been photographed after admitting to editing her Mother's Day photograph.
Prince William took a Mother's Day picture of Kate and their three children at Adelaide Cottage earlier this week, which was published on Sunday.
Royal fans began to notice at least seven digital alterations in the photograph, including Princess Charlotte's wrist and sleeve not matching and Prince Louis' fingers making a strange shape.
Kate was photographed today leaving Windsor
Getty
Subsequently, several photo agencies recalled the picture due to the manipulation that had taken place.
The Princess of Wales, 42, took to X today to take responsibility for editing the photo.
She 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.
Prince William arriving at Westminster Abbey today
Reuters
"I hope everyone celebrating had a very happy Mother’s Day. C."
Prince William and Kate were later photographed together in a car today leaving Windsor Great Park, where the couple live.
The Prince of Wales was heading to London to attend the Commonwealth Day Service alongside Queen Camilla.
According to reports in The Mail, Kate was attending a "private appointment" and would not travel to Westminster Abbey with William.
Kate had 'planned abdominal surgery' in JanuaryGettyThe royal underwent abdominal surgery in January and therefore was not planning on attending today's Commonwealth Day Service, as she is still recuperating.
She spent 13 days in The London Clinic before returning home to Adelaide Cottage to rest.
Kate is not due to begin royal duties again until at least after Easter.
LATEST ROYAL NEWS:
Kate is recuperating at Adelaide CottageGettyKensington Palace has confirmed the princess is "doing well" in her recovery.
They also reiterated her recovery timeline in a statement last month.
A spokesperson said: “We were very clear from the outset that the Princess of Wales was out until after Easter and Kensington Palace would only be providing updates when something was significant.”