A medieval king was contemplating his retirement. He had two children, a son and a daughter. By the rules of their society if the king abdicated the throne he was required to pass the powers to his son.
But the king had a problem. His son Chino was small and nerdy while his daughter Xina was strong, influential, and an accomplished warrior. And so the king would have much preferred that she inherit his powers in the roll of queen rather than to follow the rules and pass the throne to his son.