LONG WAIT TO BE MONARCH
The baby may have a long wait before becoming monarch, although it cannot be predicted when that moment will be.
"It's an impossible question to answer but looking at the present royal family, they are long-lived," said Kidd.
The current Queen is 87, and her mother, the Queen Mother, was celebrated for her longevity and died at the age of 101.
The Queen is in good health, and her son Prince Charles is also healthy. And after their reigns will come the reign of Prince William.
Kidd said it was a matter of pride for Britons that their royal family lived to such old ages.
"We are very glad that our royal family is strong and health, and obviously enjoying life because I think you have to enjoy life to live a long time," Kidd said.
When the baby is born, Prince William is expected to be in attendance, together with members of Kate Middleton's family.
Prince William is expected to phone the Queen with the good news.
The British Queen is also the formal head of state of 16 nations across the world -- including Canada, Australia, and New Zealand.
There are special arrangements for the prime ministers of these nations, as well as the British prime minister David Cameron, to be the first to be informed about the royal birth because of its constitutional significance.
The birth of the baby will be marked with celebrations across Britain and across the Commonwealth.
An announcement will also be made at Buckingham Palace. Traditionally a bulletin is placed on the railings around the courtyard, but this time the bulletin is expected to be put in a gilt frame and mounted on an easel in the courtyard.
In London, there will be several gun salutes. A 41-gun salute will be fired by the King's Troop Royal Horse Artillery in Green Park, neighboring Buckingham Palace.
There will also be a 62-gun salute at the Tower of London, fired by the Honorable Artillery Company, one of the oldest units in the British Army which traditionally marks royal events like birthdays and anniversaries with a gun salute.
A total of 62 rounds will be fired at the Tower because the basic royal salute is 21 guns, with the addition of 20 guns because the Tower is a royal palace, and a further 21 guns fired on behalf of the City of London.
The birth of the baby is also likely to be announced on digital social media outlets at the same time.
For British people, the royal birth is just another event in a summer crowded with sporting events, which have kept their attention.
In the northern industrial city of Manchester, people were going about their normal lives in hot summer weather.
Geoff Ward, aged 54 from Collyhurst, said he was waiting eagerly, but queried, "Why's it taking so long? I thought the baby was due a few days ago?"
Sarah Evans, aged 32 from Audenshaw, said, "I'm excited for Kate. I hope it goes well."
Others said they were not worried about waiting, but wished Kate and the baby well.
Alan Green, aged 24 from Sale, said, "It's a big event. I'm looking forward to hearing the news; I wish Kate and her baby well."
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