The Duke of Cambridge revealed he is 'absolutely thrilled' for the Duke and Duchess of Sussex following the birth of their son yesterday.
William, 36, shared his excitement about his nephew's arrival as he joined Kate, 37, to launch the inaugural King's Cup Regatta at the Cutty Sark, in south-east London today.
The proud uncle told well-wishers he is 'looking forward' to meeting his nephew 'in the next few days' once 'things have quietened down'. He added jokingly: 'I'm very pleased and glad to welcome my own brother into the sleep deprivation society that is parenting.'
Kate, who looked chic in a nautical-inspired outfit for the outing, shared her husband's delight, saying: '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.'
Baby Sussex arrived at 5.26am on Monday, weighing 7lb 3oz. The Duke and Duchess of Cambridge revealed they do not yet know the baby's name.
The Prince of Wales has also spoken publicly for the first time about the birth, saying he was 'delighted' at arrival of his latest grandchild.
During an official visit to Germany with the Duchess of Cornwall, Charles said: 'We couldn't be more delighted at the news and we're looking forward to meeting the baby when we return.'
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The Duke of Cambridge said he was 'absolutely thrilled' about the birth of the Duke and Duchess of Sussex's son, adding he was 'looking forward to seeing them in the next few days when things have quietened down'
The Duchess looked ready to set sail in her jaunty ensemble of a Breton stripe top, high waist blue trousers and a red clutch bag
The Duchess of Cambridge received a posy of flowers on her arrival at the Cutty Sark, where she and William launched the inaugural King's Cup regatta. The couple will go head-to-head in the sailing race off the Isle of Wight this summer
The Duke and Duchess of Cambridge arrived together for the joint engagement, which will see them announce a new sailing race. The couple will go head-to-head at The King's Cup Regatta off the Isle of Wight in August
Asked how he was feeling, the Duke of Cambridge, pictured with the Duchess of Cambridge at the event, said said: 'I'm very pleased and glad to welcome my own brother into the sleep deprivation society that is parenting.'
The Duchess of Cambridge donned a Breton striped top and £150 high waist trousers by LK Bennett for the outing
The Duchess of Cambridge gazed lovingly at her husband as they arrived for the engagement in London today
William and Kate spoke about Baby Sussex as they arrived to launch the charity King's Cup regatta, which will see the couple go head-to-head in the race off the Isle of Wight in August.
Shortly after stepping out of the car, William and Kate were quizzed over their nephew's arrival.
Asked if he had any pearls of wisdom for his younger brother, William said: 'Plenty of advice, plenty of advice. But no, I wish him all the best and I hope
