I don't understand the rules of the monarchy. Why can there be no other Queen in our lifetime?
The boys get pushed to the front of the queue. It'll be Charles, then his son William, then his
son George. And if George has a son, he'll be next. And as sons come before brothers, even Charles' brothers will never get to be King.
Assuming each of them gets a long stint on the throne, it'll be Kings for a long while yet.