Prince Charles and his wife Camilla have arrived to visit his first grandchild in hospital just after a visit from Kate's parents earlier this afternoon.
The pair smiled and waved to the raft of international media gathered across from St Mary's Hospital following the birth of William and Kate's newborn yesterday afternoon.
The Duke and Duchess of Cambridge and their new son were also visited by proud grandparents Michael and Carole Middleton today.
Kate's parents travelled to the Lindo Wing of St Mary's in London to see their daughter and William, and the baby prince who will one day be king.
It was the first visit the royal couple and their son have received since the newborn was delivered yesterday at 4.24pm, weighing 8lb 6oz.
The Middletons arrived in a black cab and were greeted on the steps of the Lindo Wing by its lead clinician Jonathan Ramsay, before they walked up to the doorway.
The couple turned and smiled broadly as they posed for a few seconds for the world's media camped opposite the building, but did not reply to the many questions shouted out by journalists.
The Duke and Duchess earlier thanked the hospital staff who delivered their baby, describing the care they and their son received as "tremendous".
The royal couple said in a statement: "We would like to thank the staff at the Lindo Wing and the whole hospital for the tremendous care the three of us have received.
"We know it has been a very busy period for the hospital and we would like to thank everyone - staff, patients and visitors - for their understanding during this time."
A Kensington Palace spokesman gave an update about the Duke and Duchess and their new son: "Mother, son and father are all doing well this morning."
It is still not known when William and Kate and their baby will leave hospital. Their departure could be this evening - though it will not be before 6pm - or possibly tomorrow.
The Prince of Wales gave his reaction to the birth earlier, saying he was "thrilled and very excited" about his first grandchild.
His wife the Duchess of Cornwall praised Charles when they visited the village of Bugthorpe in East Yorkshire, saying he would make a "brilliant" grandfather.
"I think it's wonderful news. I think mother, son and father are all well," she told the BBC.
"And I think it's a wonderfully uplifting moment for the country.
"It's very exciting and it's wonderful for the grandfather - he's brilliant with children."
William and Kate stayed overnight at St Mary's Hospital in Paddington following the birth and could spend a second night at the Lindo Wing if advised to do so by their medical team.
They have yet to announce the name of their son and it could be several days before the nation knows what the baby will be called.