When it comes to British royalty there are only two ways to become a princess. You have to either marry a prince, or be the daughter to one.
So both the leading ladies in Prince William's life are princesses, Kate Middleton who married the prince and Charlotte who was born to her dad.
While her father's children automatically inherited their titles, her children will not.
"Her children will not have titles because the royal titles go down the male line," Joe Little, managing editor of Majesty, tells PEOPLE.
That means when Prince George has children, they will automatically receive titles the way he and his sister did, even though Charlotte's won't.
But that doesn't mean there aren't exceptions to the rule.
Queen Elizabeth has offered new titles to other royal offspring in the past, including the children of her daughter, Princess Anne.
"The same [rule] applied to Princess Anne when she had her children," Little continues. "When she married Mark Phillips and they had children, they were given the option of a peerage for Mark. But they chose not to and Peter and Zara were brought up without titles."
Princess Margaret's children would not have titles either, had it not been for a special change made by her sister, the Queen.
Margaret married photographer Antony Armstrong-Jones, and their children would have been known as Mr or Miss, but just before their son was born, "the Queen made Tony an earl (of Snowdon), so that Margaret's children would have a title," says Little.
This was the sign of the times changing from traditional to modern in the monarchy.
"We were in a transitional period between the traditional times and the modern one and I think it would have felt inappropriate for the nephew and niece of the Queen to be Mr. and Miss."
Prince Harry's future children would also not carry the title of Prince or Princess either. They will be more than likely given the title of Lord or Lady Mountbatten-Windsor, their family name, because Harry's children would be great-grandchildren of the Sovereign, which will happen when Prince Charles succeeds his mother as King.
"And then they would only be eligible to be known as prince or princess if their parents choose to style them that way," says Little.
Even if Harry was named a Duke at his wedding, "the children would still be Lord first name or Lady first name Mountbatten-Windsor, unless the Queen issues letters patent to say they should be given the full style and title," Little adds.
So with all that being said, it means that Princess Charlotte could be offered the opportunity when it comes for her to bare children.
"So history could repeat itself with Charlotte," Little said.