I've never understood the fuss about Royals in England and this even further confuses me. Here:
A document is said to have been circulated privately in the royal household, clarifying Kate’s status.
Although she is the future Queen, as a former commoner Kate must show reverence to the ‘blood princesses’. This means she is expected to curtsey to those born royal, such as Princesses Beatrice and Eugenie – both in public and in private. The rule only applies when her husband, Prince William, is not present.
In his absence, she must also curtsey to other blue-blooded women in the royal household, including Princess Anne and Princess Alexandra, the Queen’s cousin.
|Blood princesses, Eugenie and Beatrice|