The Duke and Duchess of Cambridge have named their son George Alexander Louis, Kensington Palace has said. The third in line to the throne will be known as His Royal Highness Prince George of Cambridge. George was the bookmakers' favourite for the first name of the prince, who was born on Monday at 16:24 BST, weighing 8lbs 6oz. The family are at the Middleton home in Bucklebury, Berkshire, after spending a night at Kensington Palace. The Duke and Duchess had been expected to pick a traditional royal name for their son, who was born at St Mary's Hospital in London. Royal infants usually have historical names which are passed down through the generations. There have been six King George's up to now, most recently the Queen's father, although he was known to his family as Bertie. BBC royal correspondent Nicholas Witchell said Alexander was said to be a favourite of Catherine's, while Louis is William's fourth name. This is a relatively quick announcement of a name compared to previous royal babies. It was seven days before the name of a newborn Prince William was announced in 1982, and there was a wait of a month following the Prince Charles's birth in 1948. All births in England, Wales and Northern Ireland, regardless of parentage, must be registered within 42 days at the hospital before leaving or a register office.