However, it is estimated that it will cost Kate and William £727,885 ($1 million) to raise Prince Louis to adulthood. As for the littlest and newest royal's other names, he shares Arthur and Charles with both his father and his grandfather, Prince Charles, who is Charles Philip Arthur George. The Duke signed the registry at Kensington Palace overseen by a registrar from Westminster Register Office.
The new prince has a name - in fact three.
This is the first time since the Succession to the Crown Act 2013 came into effect which meant that boys and girls have equal rights to the succession.
It's insane to think it's been seven years since we were all glued to our TV screens watching Prince William and The Duchess of Cambridge tying the knot.
Louis is fifth in line to the throne.
Russian fighter jet made unprofessional intercept American aircraft P-8
Zach Harrell said, according to CNN . "And there's a safe way to do it, which basically means avoiding a collision". That interaction was met with similar criticisms from American officials, and similar rebukes from the Russians.
Mr Cambridge's gran Victoria, 74, used to stand on the side of the road and wave at the Queen Mum every year when she was being driven to the Cheltenham racecourse for the Gold Cup.
"It's unlikely they'll be asleep when William and Kate arrive home".
Locals in her hometown of Bucklebury are thrilled about the new little prince.
"The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, Prince Harry and members of both families have been informed and are delighted with the news".
No doubt the Duke and Duchess are not short of a few million as they are one of the most recognised royal couples in the world.
He joked: "We're thrice anxious now", before teasing that the couple would soon be releasing the name of their new son, saying, "You'll find out soon enough".
- James Taylor is a royal commentator from Derbyshire.