The Light Princess

When her mother dies, Princess Althea of Lagobel loses her gravity and her tears, and floats through life weightless and unable to cry. Her father, the king of a land locked in a bitter quarrel with its neighbour Sealand over water and gold, grows cold and cares only that she is married and ready for the throne. Althea slips away to the wild country between the two kingdoms, where she meets Digby, the prince of Sealand.