Princess Charlotte could get Princess Anne's title one day thanks to key rule

may only be nine-years-old, but she is also one of the most famous children in the world. As the only daughter of Prince William, 42, and Princess Kate, 43, Charlotte can often be at big royal events. The young royal has also captured the hearts of royal fans over the last year as she has grown in confidence, accepting flowers from fans and even posing for the occasional selfie.

While Charlotte at the moment has no working role in the family and will remain in education for a number of years yet, it is believed she is one day set to be a key figure in the monarchy.

As third-in-line to the throne, there is no doubt Charlotte will support her grandfather the King as he continues his role, along with supporting her father and her elder brother when they also take to the throne. However, Charlotte could also be set to inherit an important title herself that is currently held by Princess Anne.

For a number of years the King's only sister Princess Anne has proudly held the title of The Princess Royal.

This title is typically given to the eldest daughter of the monarch and was bestowed on Anne when her mother Queen Elizabeth II was on the throne.

While the late Queen has now passed, and Anne's brother is head of the monarchy, the Princess has kept the title and will keep it for the rest of her life.

This will also be the case if Anne is still alive when becomes King, as the inheritance of the title is not guaranteed if the previous holder is still alive.

The title is also not automatically given to the monarch's eldest daughter and instead has to be granted to her by the monarch.

While it has not been confirmed, and has most likely not been brought up in the wider family, it is believed will give the title of Princess Royal to his daughter Charlotte in the future when he is King and when Anne is no longer here.

If Anne passes away while King Charles is still on the throne, the title is likely to not be given to anyone until 's reign.

The title is also likely to be only given to the nine-year-old royal in the future when Charlotte has finished her education and has had a thought about her own future goals, with William and Kate reportedly both keen for their