The princess canceled plans to attend the horse racing event on Wednesday as she tries to find the “right balance” in her recovery from cancer, Kensington Palace said.

Catherine, Princess of Wales, was not at Royal Ascot on Wednesday, with a royal source citing her need for balance as she returns to public engagements after being treated for cancer last year.

Kate Middleton, the Princess of Wales, recently appeared alongside Prince William, as well as their children Prince George, Princess Charlotte and Prince Louis at Trooping the Colour.