This means that Princess Charlotte has a far higher chance of becoming Queen one day, than her great-aunt Princess Anne ever did. When Anne was born she was second in line to the throne, however, upon the birth of her younger brother Prince Andrew, she moved down to third in line, and then fourth when her youngest brother Prince Edward was born.
Currently, Prince George is second in line to the throne after his father Prince William who is first in line. George is therefore the direct heir and future King as William and Kate’s first-born child. That Princess Charlotte would become Queen is still unlikely as long as George wants the job. If the rules hadn’t changed then when Charlotte’s younger brother Prince Louis was born, she would have moved down to become fourth in line, and he would have taken her current spot as third in line to the throne.

Instead, as it stands, Charlotte will remain in her place in the line of succession just behind her elder brother George until he has children of his own – which is a long way off, given the royal youngster is only 11 years old.
It’s still only a slim chance that Charlotte would ever be Queen, but if George abdicated his position without having any children as his heirs, then Charlotte could potentially become the monarch.
This happened in 1936 when a childless Edward VIII gave up his position as King to marry Wallis Simpson – an American divorcee, which created a conflict around him remaining monarch because he was also head of the Church of England, which did not allow divorced people to remarry whilst their former spouse lived. After Edward abdicated, his brother King George VI took over – the late Queen Elizabeth’s father, changing the line of succession forever.