The Duke and Duchess of Cambridge have named their third child Louis Arthur Charles, according to BBC.
A tweet from Kensington Palace confirmed the baby would be known as His Royal Highness Prince Louis of Cambridge.
The new prince is fifth in line to the throne.
Louis is one of the middle names of Prince William and of the new prince’s brother, George.
Arthur is also one of the duke’s middle names, and was a middle name of King George VI – the Queen’s father.
Bookmakers had Arthur as the favourite name for the prince, followed by James and Philip.
On Thursday evening, Prince William told reporters that they were still deciding on a name, saying: “I’m working on that.”