The Princess of Wales has not yet been established as a Royal Lady of the Order of the Garter and was therefore not allowed to participate in the service and procession yesterday.
She instead wore a gorgeous black and white polka-dot Alessandra Rich dress and watched from the side lines alongside the Duchess of Edinburgh while the bulk of senior working royals were out on force for the staple event.
Queen Camilla only recently became appointed to the honourable order with the late Queen Elizabeth II bestowing her the title last June, the Express reports.
However, it's perhaps now time for King Charles to upgrade his daughter-in-law and future Queen to the order as well.
Kate's exclusion from one of the most important ceremonies in the royal calendar meant the Princess looked like a royal outsider as she was not allowed to dress in the same special robes.
While the honour tends to be reserved to royals born into the Royal Family and not those who marry in like Kate, there is a precedent for the spouse of the monarch and heir to be installed into the order which has been done so in the past.
Additionally, Kate and William have taken on an increasing amount of workload since other royals have relieved themselves of royal duties.
Camilla was installed before King Charles became monarch and Prince Philip was previously appointed as a Knight of the Order of the Garter in 1948, one year after his wedding to Princess Elizabeth when he was the spouse of the future heir.
Elizabeth wouldn't become Queen for another four years when Philip was was given his title.
The Queen Mother was appointed to the order just days after her husband King George VI unexpectedly succeeded the throne following his older brother Edward VIII's shock resignation.
However, Kate, who is wife of the future King, is still waiting to be invited to join the oldest and most senior order of chivalry in Britain.
Royal members of the order are also not limited in number nor do they count towards the limit of 24 which applies to other members.
The current membership is five shy of the limit even after the two new instalments of Baroness Ashton and Lord Patten.
It's likely that Kate will soon be appointed to the Order of the Garter given her dedicated work as a senior member of the Royal Family.
The mum-of-three has championed pioneering work on early childhood and campaigns on multiple significant issues such as mental health and sports charities.
The Princess of Wales has also stepped up her responsibilities since the late Queen's death and taken on more work due to the Firm's diminished number of working royals since Harry and Meghan left the royal family and Andrew was forced to step down.
The King is likely to recognise Kate's efforts with her valuable work and how the Princess also boosts the popularity of the Firm too as she often appears at the top of the royal polling.
A promotion for the Princess may come soon as the Firm's ratings have taken a hit in recent months.
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