RAF Valley, where Prince William serves as a Search and Rescue pilot, were among the first to offer official congratulations to Flight Lieutenant Wales and The Duchess of Cambridge on the birth of their first child:
We’re all delighted to learn that Flight Lieutenant Wales, and The Duchess of Cambridge are now proud parents of a new born son.
We wish them all the very best for the future.
From everyone at RAF Valley, congratulations.
Prince William is also Colonel of the Irish Guards, who celebrated in their own unique way at their barracks at Aldershot and in bases in London, toasting the Royal baby with a traditional glass of Irish Stout. Their Commanding Officer, Lieutenant Colonel Ed Boanas said:
On behalf of all ranks 1st Battalion Irish Guards, I send our warmest congratulations and best wishes to the Colonel of the Regiment and HRH The Duchess of Cambridge on the occasion of the birth of their son, with the heartfelt hope that he has a long and happy life.
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As news of the royal birth is celebrated around the globe a flood of souvenirs and memorabilia will go on sale to mark the occasion.
In London and around the world politicians, celebrities and members of the public have been celebrating the news of the royal birth.