Thank you for answering ! That's where I have some troubles because my IC needs to impact my MC in some way ; I could find a way to do it if their concerns were Progress and Impulsive Responses for example, but The Past and Memory ? It's harder honestly, because it can get into a black and white argument really easily (the one driven towards the truth and objectivity, the other holding on to her own subjectivity and biases).
It's great that you talk about family event because it somehow describe what I intend to do. In this story the two of them are sisters, the MC being the eldest - 18 - and the IC the youngest - 14 -. They don't have a bad relationship per se but there's a lot of misunderstandings and problems of communication between them (explaining the RS concern of Understanding). But both of them are also super heroes who fight off each other because they don't know the other's identity ; and it is both their civilian and heroic selves, as opposed to their relationship as sisters, that represent the MC and IC perspective. I have some ideas for the IC concern of Memory (her notoriety as a civilian, a veteran hero, a middle-school girl, a sister or a daughter ; nobody can quite understand her because of how different their recollections of her are. Her own memories, which are driving her towards doing good or bad things. How she forces her sister to remember things in general, especially about them and herself. Determined to make a big impact in the world, as a hero, and in her family, as a civilian.) Troubles arise when it comes to make the MC concern of The Past different from this concept of Memory, and in such a way that the IC perspective will really challenge (and then change) her worldview.