GORGEOUS bundle of joy Arthur Lau will have two unique reasons to celebrate future birthdays.

Not only is he the first boy for his proud St Albans parents Mariann and David Lau – who already have four daughters – but he shares the same birthday as our future king, the Duke and Duchess of Cambridge’s new son.

And because of his regal name, wee Arthur has already been dubbed the “prince of the family”.

While millions of people on Monday waited with bated breath for the arrival of the royal baby – third in line to the throne – anxious parents to be at Watford Hospital were also waiting to welcome their own newborns into the world.

As scenes of jubilation erupted across the globe at news of the birth of the as-yet-to-be-named infant prince, celebrations also were in evidence throughout the maternity ward at Watford.

Sixteen babies were delivered on the same day as the future monarch, four of whom were from St Albans.

Several were born in the hospital’s new birth centre, while the remainder were delivered in the main maternity unit or at home.

While the Duchess gave birth to her 8lbs 6oz son at 4.24pm, Arthur, weighing 8lb, was born at 6.10am on Monday, after a two hour labour for Mariann.

Arthur is of course the regal name of the main character in Arthurian legend – a Sixth-Century king.

Commenting on her baby’s name, Mariann said: “We didn’t even think about the relevance of such a name until our friends started making remarks about him being the prince of the family!”

The couple are delighted their daughters now have a brother, and after giving birth five times Mariann has a good piece of advice for new mum Kate: “Sleep when the baby sleeps”.

Arthur and the other 15 babies delivered at Watford on July 22 are now entitled to receive a royal silver coin as they were born on the same day as the Duke and Duchess of Cambridge’s son.

According to folklore, crossing the palm of a newborn baby with silver or offering them a silver penny is a way of wishing them a wealthy and healthy life.

Also passing on best wishes to the new addition to the royal household is Lord Lieutenant of Hertfordshire, the Countess of Verulam, the Queen’s representative in the county. She said she was “absolutely delighted to hear the news of the safe delivery of the prince”.