Princess Anne, the Queen 's only daughter, is 16th in line to the throne - behind Prince Andrew and Prince Harry - despite being the late Monarch's second oldest child. 'Primogeniture' determines how children inherit their parents' estate, and rules that apply to the rest of us also apply to the Royal Family and affect their chances of becoming King or Queen.
But due to a law enacted in 1701, the Royal Family operates under 'male-preference primogeniture', where male children receive a more prominent position than females. The Queen overturned the rule in 2013 under the Succession to the Crown Act, which gave women equal rights, but it wasn't backdated so Princess Anne's position remained unchanged.
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Since the 2013 change, succession now goes to the next member of the Royal Family in birth order, applying to anyone who was born after 2011.
This means that Princess Charlotte, the daughter of the Duke and Duchess of Cambridge, will be the first female heir who is not displaced by her younger brother, Prince Louis.
The Royal family's website has a full list of succession, but ahead of Princess Anne are Prince Charles, Prince William, Prince George, Princess Charlotte, Prince Louis, Prince Harry, Prince Andrew and Princess Beatrice, among others.
Since King Charles III ascension to the throne, many roles in the Royal Family have changed and some have been made Counsellors of State - who can stand in for the Monarch if he is ill, or absent.
The current Counsellors of the State are Queen consort Camilla, Prince William, Prince Harry, Prince Andrew and Princess Beatrice - but again, not Princess Anne.
That's because the Counsellors of State include the spouse of the Monarch and the next four people in line of succession over the age of 21.
Some royal watchers have been shocked by the fact that Princess Anne is not a Counsellor of State because she is often called the hardest-working member of the Royal Family.
In an annual tally of engagements, it is Anne who is often at or near the top of the league tables.
In royal commentator Victoria Arbiter's view, Anne has not been "overshadowed" as much as she has been overlooked and "ignored by the media."
In 2021, Princess Anne was named the year's hardest working royal, who completed 387 official engagements, ahead of King Charles III, then a prince, who carried out 385.
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