The latest addition to the Royal family is expected to become the new Earl of Dumbartion, according to royal tradition.
The Duchess of Sussex has given birth to a son, Buckingham Palace has announced. The baby boy weighed 7lb 3oz and was born at 5.26am.
The Duke of Sussex was at his wife's side and mother and baby are both doing well, the palace said.
Unless the Queen steps in at the last minute, the baby will not be an HRH or a prince due to rules limiting titles within the royal family which were introduced by King George V more than 100 years ago.
And so the boy is expected to be known as the Earl of Dumbarton - because a first son of a duke is allowed to use one of his father's other lesser titles as a courtesy title.
Harry was made Earl of Dumbarton by the Queen on the morning of his wedding, as well as being given a dukedom.
The Queen stepped in ahead of George's birth to issue a Letters Patent to ensure all the Cambridges' children would have fitting titles, but that was done well ahead of time and this royal baby is much further down the line of succession.
Under George V's rules, Harry and Meghan's child and any future children would eventually become princes or princesses when Charles becomes king, because they would be the children of a son of a sovereign.