What Happens To Kate Middleton If Prince William Dies First?
The current rules for the British royal family line of succession state that the first-born child of the current monarch is first in line to ascend to the throne following the monarch's death. The next person in line is that person's eldest child, and then each subsequent child in order from oldest to youngest. For example, when King Charles III passes away, Prince William will become the king. Next in line would be his son, Prince George. After all of William's children, the line of succession continues with Prince Harry, all of his children, and then Charles' siblings, their children, and their grandchildren. To be eligible for the throne, a royal must be a member of the Church of England, and Parliament has power regarding ascension — they can remove a monarch from the throne if they deem it necessary. If a royal is under 18 when their predecessor dies, a regent works in their place until the royal is 18 and can be crowned.
The Succession to the Crown Act from 2013 changed some of the rules regarding ascension to the throne. For example, younger sons can no longer leapfrog over older daughters in the line of succession, and the rule that royals who marry Roman Catholics cannot ascend to the throne has been disbanded.
The coronation of King Charles III in May 2023 has people wondering what Kate Middleton's title will be when Prince William is crowned, and what will happen if, after he's named king, he dies before Kate?
Kate may become Queen Mother when Prince George is crowned
When Charles became king following his mother's death, his wife Camilla earned the official title of Queen Consort. The difference between a queen and a queen consort is political power. After the coronation, Camilla's official title became just Queen Camilla. However, that does not change the amount of power she holds, and she is still the queen consort.
In the future when Prince William is crowned king following King Charles' death, Kate Middleton will become the new queen consort, Queen Catherine. As all consorts before her, she will not hold any political power with this title, but she can continue her charity work and other royal duties while standing alongside William during his reign.
Queen Elizabeth II's mother, Queen Elizabeth, was also a queen consort. After Elizabeth II was crowned queen following her father's death, her mother became the queen mother. If the future-King William passes away while Kate is still alive and Prince George takes the throne, Kate can become the new queen mother if she would like. According to royal expert Marlene Koenig, " ... she can choose to be styled as [Her Majesty] Queen Catherine, the Queen Mother" (via Town and Country).
However, if Charles dies first, Camilla's title would differ from Kate's
If King Charles dies before Queen Camilla, she is unable to take the title of queen mother the way Kate Middleton could. The reason is because Camilla is not Prince William's mother. Instead, she could become the queen dowager, which is the official name for a widow of a king. Kate would technically also be a queen dowager but could choose the queen mother title because she is Prince George's mom. Like whoever holds the queen consort or queen mother titles, a queen dowager does not have the same kind of political power a queen has.
There are no rules against a widowed queen remarrying, so if Camilla and/or Kate outlived their husbands, they could do so if they wished. However, if they remarry, they may lose their official titles and instead take on the titles of their new husbands. Professor Rob Cover explained how a new monarch might be able to make a declaration of what they want someone's royal title to be, so when George becomes the king, he could decree that his mother be able keep her titles, even if she remarries. The prime minister and cabinet would have to agree on the titles in that scenario.