Now the Princess Royal, 72, and her younger brother Prince Edward, 58, can carry out the constitutional duties of their older brother, King Charles III, if he is abroad or unwell.

Princess Anne / Photo: Associated Press

The Councilors of State Bill received royal assent and became law the next day.

By law, Anne and Edward are now Charles III's Councilors of State for life.

The bill was introduced in the British parliament and quickly considered by both houses to avoid a potential "awkward constitutional problem" involving Princes Andrew and Harry, the BBC reports.

King Charles III and Prince Andrew / Photo: Associated Press

The position of State Councilor usually belongs to the wife of the sovereign, followed by the first four persons in line to the throne over the age of 21.

At once they are Queen Camilla, Prince William, Prince Harry, Prince Andrew and Princess Beatrice (daughter of Prince Andrew).

But since Princes Harry and Andrew are no longer high-ranking members of the royal family, Parliament has seen fit to expand the list of people who can stand in for the king to include Princess Anne and Prince Edward.

King Charles and Prince Edward / Photo: Associated Press

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