The baby was born under the sign of the crab, meaning he will be in touch with his emotions and love a cuddle from mum and dad.
He is the same star sign as dad William, 31, and his late gran Princess Diana, whose down-to-earth, caring characters have seen them champion a string of good causes.
Carrying on such traits will make him a perfect candidate for the demanding role of Prince, understanding the challenges of ordinary people across Britain and the globe.
The boy has also picked an unusual time to come into the world, on the cusp of two star signs and during a Full Moon.
If he had been born after 4.57pm yesterday, when the signs changed, he would have been a trailblazing Leo.
But rather than a fiery, decisive and limelight-loving Leo, experts reckon he will be a sensible lad who can show great sympathy and compassion for others.