11/06/2017 11:57 EST | Updated 11/06/2017 12:19 EST

Princess Charlotte Can Thank The Queen For Securing Her Succession To The Throne

The two-year-old is fourth-in-line after Prince Charles, Prince William, and Prince George.

Once upon a time, Princess Charlotte could have been bumped down to fifth-in-line to the throne if the third royal baby was a boy. However, she can now thank her great-grandmother, Queen Elizabeth II, for changing this (outdated) royal rule before her birth.

Under the Act of Settlement of 1701, all male siblings could skip ahead of their sisters in the line of succession, no matter their birth order, PopSugar reports. This is known as male primogeniture, and unfortunately meant the Queen's second child and only daughter, Princess Anne, was bumped from third-in-line to the throne to fifth after the birth of her siblings Prince Andrew and Prince Edward.

Pool/Samir Hussein via Getty Images
Princess Charlotte in Berlin during the royal tour of Poland and Germany in July 2017.

In 2013, Her Majesty decided to change this sexist system with the Succession of the Crown Act, which essentially replaced male primogeniture with absolute primogeniture. The act then became official in March 2015, just two months before Princess Charlotte was born, securing her place as fourth-in-line to the throne.

The new succession laws now apply to all royals born after Oct. 28, 2011. That year, 16 British Commonwealth countries — including Canada, Australia, New Zealand and the Bahamas — voted to make the changes. At that time, Britain's then-Prime Minister David Cameron said, "The idea that a younger son should become monarch instead of an elder daughter simply because he is a man ... this way of thinking is at odds with the modern countries that we have become."

Earlier on HuffPost:

Thanks to the new succession laws, Prince Charles is first-in-line to the throne, followed by Prince William, Prince George and Princess Charlotte. The third royal baby, regardless of gender, will then be fifth-in-line, followed by Prince Harry.

The royals have always had very particular rules regarding succession and titles. For example, another rule is that Prince George's future children will receive royal titles, but Princess Charlotte's won't.

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(L-R) Queen Elizabeth II, Prince Philip, Duchess of Cambridge, Princess Charlotte, Prince George and Prince William, Duke of Cambridge looking out at the Trooping the Colour parade in June 2017.

Lucy Hume, associate director of expert etiquette company Debrett's, explained this to Town & Country saying, "Royal titles are inherited through sons, so if Princess Charlotte has children they would not automatically inherit the titles HRH, Prince, or Princess," she said.

However, Hume added that there can be exceptions: "The monarch may offer to bestow a royal title upon his or her daughter's children."

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