LONDON, July 21 (Xinhua) -- The baby which Catherine, Duchess of Cambridge, expects to be born soon will mean that there are four generations of the British royal family either on the throne or waiting to succeed, the first time that has happened for over 100 years.
Charles Kidd, editor of Debrett's Peerage, told Xinhua, "The baby is very significant because it is the next generation in line to the throne after its father the Duke of Cambridge."
The baby will mean that there are three generations of the royal family waiting to succeed to the throne -- first, Prince Charles, then his eldest son William and the new baby.
"It has been 119 years since there was this exact line of succession, with three generations, back in the time of Queen Victoria," said Kidd.
"Her great grandson was born in 1894 and he became Edward VIII, who then abdicated and became the Duke of Windsor. It's exactly the same - in 1894 Queen Victoria's eldest son's eldest son had a child," said Kidd.
So, given good health, the baby will become the monarch.
"In the fullness of time, and as one generation succeeds another. This is how it works," said Kidd.
One thing has changed, however.
Kidd explained: "There has been this Act of Parliament since earlier this year which says that the sex of the child, if it is born female, will not alter in the line of succession if she has a younger brother in due course. She will take precedence over a younger brother."
"This is a very big difference to our royal traditions. It is really the most significant change in royal law since the Act of Settlement in 1701," Kidd added.
The Act of Settlement ensured the succession to the throne of Queen Elizabeth's direct successors the Hanoverians, legalizing their legitimate claim to the throne above that of their relatives the Stuarts on the grounds of religion.
Whatever the sex of the baby, we already know what style it will be given.
"It will be styled His/Her Royal Highness (HRH) and the title is Prince or Princess. Then the Christian name, and then 'of Cambridge'," said Kidd.
Prince William and Kate have also followed the precedence of his father, grandmother, and great grand-father (Prince Charles, the Queen, and George VI) and had a baby just a few years after their wedding.
"There has not been any sort of prolonged wait for babies after the marriages in the royal family," said Kidd.
Whatever the reasons, the swift appearance of babies does mean that a new generation is born and the succession is secured.
The only recent king to break from this behavior was the ill-fated Edward VIII, who was 41 when he succeeded to the throne in 1936 and who had not married.
His plan to marry a divorced American, Wallis Simpson, led to his abdication from the throne within a year. Perhaps a baby provides foundations for the parents.
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