Little brother and little sister with an attraction to trouble. Anna and Hiro both operate as the youngest of their siblings and the ones who take risks and initiative in their families,
In terms of each other, Hiro and Anna offset each other perfectly. Anna brings joy and optimism to Hiro's confused and cynical mindset, while Hiro grounds Anna with practicality in the same manner as Kristoff. This can either work as a close friendship or even a romantic relationship. How they come to know each other differs between stories, either accomplished through some form of time travel or an AU scenario that permits their coexistance.