The Duke and Duchess of Cambridge have welcomed a new addition to the family, and just like Prince George and Princess Charlotte, their third child will have a lasting impact on the line to the throne.
The new prince has also made history - he is the first royal boy who will not be ahead of his older sister in the line of succession.
After the Succession of the Crown Act came into force in 2015, it officially ended the rule that a younger son could displace an elder daughter in the line of succession. This means Princess Charlotte will remain fourth in line to the throne, regardless of her younger sibling's gender. The new baby has become fifth in line.
In a statement announcing the birth, Kensington Palace said: 'The baby is fifth in the line of Succession after His Royal Highness The Prince of Wales, His Royal Highness The Duke of Cambridge, His Royal Highness Prince George of Cambridge and Her Royal Highness Princess Charlotte of Cambridge. He is styled His Royal Highness Prince [name] of Cambridge.'
The royal who has been most affected by the birth of William and Kate's third child is Prince Harry. Before his birth, William's younger brother was fifth in line to the throne, behind Charlotte. Now his new nephew has moved him further away from the crown into sixth place - but it's unlikely that the newest member of the Cambridge family will ever take the title of king. Should Prince George have children in the future, they will push Charlotte and their new sibling further down the line of succession. Similarly, if Harry and Meghan have a child, he or she will come ahead of Prince Andrew.
The line of succession as it currently stands is:
1. Charles, Prince of Wales
2. William, Duke of Cambridge
3. Prince George of Cambridge
4. Princess Charlotte of Cambridge
5. New (still unnamed) royal baby
6. Prince Henry [Harry] of Wales
7. Andrew, Duke of York
8. Princess Beatrice of York
9. Princess Eugenie of York
10. Edward, Earl of Wessex
A third-born child has yet to become king or queen in the House of Windsor. However, as the BBC points out, William IV, the third child of George III and Queen Charlotte, was not expected to reach the throne. Yet he ruled from 1830 to 1837 after his two brothers died without leaving a legitimate heir.
