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.

Catherine has slowly returned to public events after cancer treatment and had been expected in the procession of Royal Ascot, but she abruptly canceled.