Once upon a time, in a country which now exists only in the earth which houses its old stones and the breath that houses its old stories, there lived a king and a queen. The queen had a daughter and a son, and then had no more children, for inheritance rules were tricky at the best of times, and became no simpler for those of royal blood.
The young boy was taught to fight with and without arms, was taught to care for his animals and to clean his weapons, to be polite at court and to be impolite without causing a war.
The young girl was taught to fight with her voice, to cut as deeply as her brother. Where her brother was taught only, "You can go this far and no further," she was taught each intricacy: how to form or strengthen an alliance, how to inspire an attack that would take few lives but give an excuse for conquest. When her brother was learning to fight with fists or swords, she would learn dance steps, a dozen curtsies, a dozens of implications in a single sentence. When he was caring for his animals and weapons, she would practice what she was learning with forgiving friends of the family.
As they grew, they began practicing in earnest. The prince would duel, and the princess would work out treaties, forming personal alliances so that the country's power would not fade if those loyal to the current monarch liked the prince or princess less. They each paid close attention to their own lessons, both what they were being taught and how they were being taught it. Of course they did.
Quietly, when most of the castle slept and the guards looked on with approving smiles or pretended not to see, son and daughter met. He handed her a sword or a mace or nothing at all, and they fought in the dirt. She met him with a book or a fork or a smile, and they play-acted through diplomatic scenes.
So it came to pass, with very little fuss, that the prince married and became a king fierce and diplomatic, and the princess became a warrior who knew how to avoid a fight as easily as she knew how to win one. And, when she was home from war and he from discussions of treaties, they would meet in the same field and tell each other what they had learned.
Some things never change.