New parents the Duke and Duchess of Sussex were jokingly welcomed into the “sleep deprivation society” by Prince William, amid continuing speculation on potential names for the new royal baby. 

The Duke and Duchess of Cambridge were  at the Cutty Sark in Greenwich, near London, their first public engagement since the birth, when they were asked about their new nephew. 

Prince William quipped that he was happy to welcome his brother Prince Harry to the “sleep deprivation society” after the Duchess of Sussex gave birth, more than a week over her due date, at 5.26am on Monday May 6.

It is thought the infant was delivered at the private Portland Hospital in London, although that has not been confirmed by Buckingham Palace. 

It was widely reported in the run-up to the birth that the duchess hoped for a home delivery at the couple’s Windsor residence, Frogmore Cottage.

Prince William said: “I’m very pleased and glad to welcome my own brother 
into the sleep deprivation society that is parenting.

“I wish him all the best and I hope in the next few days they can settle down and enjoy having a newborn in their family and the joys that come with that.”

The couple were visiting the famous tea clipper as they launched the inaugural King’s Cup Regatta, which will see the sporty royal couple go head-to-head as the skippers of rival boats in an eight-strong field on August 9, off the Isle of Wight.

The event will raise funds for eight of the charities they support, including Child Bereavement UK and Centrepoint. 

Meanwhile the Prince of Wales, now a grandfather of four, said he was “delighted” by the arrival of baby Sussex. 

Prince Charles and the Duchess of Cornwall were congratulated and given presents by well-wishers during a four-day trip to Germany.

Shortly after arriving in Berlin, Prince Charles said: “We couldn’t be more delighted at the news and we’re looking forward to meeting the baby when we return.”

German President Frank-Walter Steinmeier later presented him with a teddy bear wearing blue clothes.

The Duchess of Cambridge added: “We’re looking forward to meeting him and finding out what his name’s going to be. These next few weeks are always a bit daunting the first time round so we wish them all the best.”

She added: “It’s such a special time. Obviously with Louis and Charlotte just having had their birthdays it’s such a great time of year to have a baby, spring is in the air.”

Harry and Meghan’s son, who has not yet been named, is seventh in line to the throne, behind the Prince of Wales, the Duke of Cambridge and his children 
– Prince George, Princess Charlotte and Prince Louis – and Prince Harry.

However, he will not be given the title of Prince or HRH, unless his great-grandmother the Queen intervenes.

Restrictions dating back to the reign of George V decree that HRH status should lapse for relatives more than two generations below the monarch who are not in the direct line of succession.

The Queen issued a special ruling to ensure that all of Prince William and Kate Middleton’s children would be HRH, not solely Prince George as the first-born.

However, it has been suggested Prince Harry and his wife will be inclined to shun titles for their son, who is also the first member of the Royal Family entitled to dual US nationality and the first with African heritage.

Bookmakers have Spencer as their odds-on favourite for the new royal’s name, at 4-1. James and Alexander are also hotly tipped with odds of 5-1.

However, there was speculation that the couple might seek to make a nod to the infant’s US  heritage, with Theodore attracting odds of 12-1. 

The name would conjure up references to acclaimed US president Theodore Roosevelt, one of four whose face is immortalised on the side of Mount Rushmore.

In the US, the arrival of the first British-American royal baby sparked a flurry of articles, especially on its significance as a symbol of modernisation. 

In an editorial, the New York Times said he “represents change for the oldest of houses... He is the first multiracial baby in the British monarchy’s recent history, an instant star in a country where multiracial children make up the fastest-growing ethnic category.”

However, a CNN opinion piece cautioned that “the presence of these mixed-race symbols in positions of power doesn’t automatically translate into more power for people of colour”.

Meanwhile, Fox News columnist Kristina Hernandez simply noted that Prince Harry’s gushing praise for his wife’s bravery during the birth was “a message that more women need to hear”.