Kate carried the new royal baby – whose name has yet to be announced – in her arms, with William by her side.
She carefully handed her precious baby to proud father Prince William to hold for more photographs and while they answered a few questions.
Prince William said: "He's got a good pair of lungs on him.
"We're still working on a name."
Kate said: 'It's been very emotional and such a special time. I think any parent will know what this time is like."
Prince William joked "He's got her looks, thankfully!" while Kate interjected "no, no, no."
In the few minutes they were before the public the royal couple showed a close and loving bond for each other and their new baby.
The couple then turned back into the hospital before re-emerging to get into a Range Rover with their son in a Britax Baby-Safe Infant Carrier car seat.
Prince William proved adept at quickly installing the baby car seat in the backseat, while Kate sat next to her baby, tenderly touching his cheek. Then man-of-action William drove his wife home.
Some royal fashion followers were quick to point out the similarities between the Duchess of Cambridge's pale blue crepe de chine dress and the pale green dress Princess Diana wore when she left hospital after the birth of Prince William 31 years ago. While not having any claim to fashion know-how, here at Parentdish we would say that yes, the dresses are both spotty and um, that's it, really.
Earlier in the afternoon, Kate's parents Carole and Michael Middleton visited their new grandson, and later Prince Charles and Camilla, Duchess of Cornwall, also popped in to meet the latest royal. At a reception at Buckingham Palace the Queen, great-grandmother to the new prince, told a visitor she was 'thrilled'.
Kate and William released a statement thanking the nurses, doctors and other staff at St Mary's Hospital, saying: "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."
The new family returned to their temporary accommodation, Nottingham Cottage, in Kensington Palace, but were spotted arriving at Kate's family home in Bucklebury, Berkshire, today (Wednesday, July 24).
Refurbishments are continuing to their new apartment in Kensington Palace, the former home of Princess Margaret - proving right that truism about babies arriving immediately before or after house moves!
Prince William has two weeks paternity leave from his job as a search and rescue RAF pilot based in Anglesey, North Wales.
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