Kate Middleton and Prince William are taking on new royal appointments.

Kate Middleton and Prince William are taking on new royal appointments.

On April 23, which happens to be the sixth birthday of the Prince and Princess of Wales’ son Prince Louis, King Charles announced several new appointments, including for members of the royal family.

The King, 75, appointed his daughter-in-law Princess Kate, 42, as the Royal Companion of the Order of the Companions of Honour. In a history-making twist, she is the first Royal Companion named to this order.

The Order of the Companions of Honour was founded by King George V in 1917 to recognize outstanding achievements in the arts, sciences, medicine and public service. Members are limited to 65 at a time (although people from outside Commonwealth countries can be counted as additional honorary members) and currently include David Attenborough, Elton John, Anna Wintour, Judi Dench and Maggie Smith.

Princess Kate’s new appointment from King Charles comes as they are both undergoing treatment for cancer.

“He has always had a very good bond with her. I don’t think it is presumptuous to say that she is like the daughter he never had,” royal biographer Sally Bedell Smith recently told PEOPLE. “He shares with William an impulse to protect her. They are in this together, Kate and the King.”

Buckingham Palace said that King Charles was “so proud of Catherine for her courage in speaking as she did” to announce her cancer news on March 22.

Prince William, 41, was appointed by his father to be Great Master of the Most Honourable Order of the Bath. The role had been vacant since 2022 after King Charles, who held the role from 1974 to 2022, acceded to the throne.

The Most Honourable Order of the Bath was established by King George I in 1725 but is believed to originally date back as far as the eighth century. It is awarded to members of the military or civil service for exemplary service.

Queen Camilla also received a new appointment from her husband as the Grand Master and First or Principal Dame Grand Cross of the Most Excellent Order of the British Empire.

The Order of the British Empire was established by King George V in 1917 to honor a broader cross-section of society, both military and civilian. It comprises five classes, the two most senior of which makes the recipient a knight or dame.