heiress apparent

— “Dear me!” said I, “what a sweeping charge of folly you are bringing against nearly the whole sex, which, after all, is only another version of what I said, namely, that women were great fools to marry. I have no doubt there are exceptions, and that the poor Princess Charlotte, for instance, found a husband the most docile, irreproachable, and obedient of created beings, and that all heiresses apparent to thrones will do the same;[…]”