The Princess of Wales honored her father-in-law, King Charles, in the traditional way and made a subtle homage to Queen Elizabeth during Monday’s church service.

It goes without saying that Westminster Abbey is a place that holds great meaning for the Prince and Princess of Wales: After all, Prince William and Kate Middleton tied the knot there in 2011. It’s also home to Kate’s annual “Together at Christmas” concert and where they toasted King Charles’s coronation—a moment that placed them next in line to the throne—back in 2023.

Middleton — who scaled her royal schedule back last year due to her cancer diagnosis — joined Prince William, King Charles, Queen Camilla, Princess Anne, Prince Richard, Duke of Gloucester and Birgitte, the Duchess of Gloucester, for the commemoration.

The Princess of Wales joined members of the royal family at Westminster Abbey on Monday, March 10, to celebrate Commonwealth Day. As part of the service, Kate and Prince William processed behind King Charles and Queen Camilla. They were followed by Anne, Princess Royal, as well as the Duke and Duchess of Gloucester.

Kate Middleton paid a subtle tribute to Princess Diana and Queen Elizabeth II with her fashion as she attended the Commonwealth Day celebrations in London March 10.