I am currently writtng a story about basically a ten year old "chosen one", who is supposed to save the world from some evil death cult. In summary he is protected by divine powers and can do miracles mostly related to healing the sick. He has an adoptive sister, who is in her late teens and has the exact opposite power. She can make everything around her wither and die. She however seldom uses it as she has a rather good nature. They both saw their parents die gruesome deaths. Now I made them end up with some resistance fighters, where I want the protagonist grow. That's where I am now stuck: and not sure how to develop his character. He is supposed to be in general; kind and grow up amidst of adults with high expectations of him. His only family is his sister. How do you think this would realistically affect him?
Is there any kind of personal conflict inside him? Not on the level of 'what does he want?', but something within him that causes issues? If he's a resistance fighter, maybe he didn't want to be and struggles with not saving his enemies when he knows he could heal them in an instant? Something like that. In my experience, characters can't be interesting when they're just under outside pressure. You could try finding two motivations that work for him, maybe he enjoys the security of his dystopian home (mind control means no crime, after all), but knows he should fight it.
In thinking about a child who grew up with very high expectations of him without a great deal of exposure to regular childhood issues might not have the chance to develop normally in a number of areas. He could potentially have some difficulty empathizing with others, or perhaps a highly focused fear of failure. Not sure how this fear of failure might manifest, but it could be such that he fears taking on challenges that he thinks he will fail. I would recommend thinking of how a child would develop under this environment and what he might be missing out on. Does he have basic conflict resolution skills that are typically learned in the school yard. Perhaps he is the "always right" type of person, and can't handle being wrong. I'm not sure if any of this helps, but looking for interesting personality quirks might be found by searching home school psychological issues. Also google why it is important for children to interact with other children. Good luck
This is making me think of Avatar: The Last Airbender. Aang begins to be isolated from his friends as they have difficulty accepting that he is still a person as well as being the Avatar. Unable to cope with his responsibility, he runs away, and does not tell the siblings who found him of his identity. It's quite hard to explain, but the show gives a very good portrayal of kids forced to take on adult responsibilities.
Not to be a fly in the ointment, but if you don't know your protagonist like they are your best friend from high school, you may not be ready to start working on your narrative. Your trying to figure out their motivations. That's like...the whole thing right there. Ask yourself, what do you want the reader to think about this character? What do you want their reaction to be to them? Plot points are important, but that solar system revolves around the gravity of the how and why of your protagonist's decisions. Look at it like this: 99% of people in the world would totally brush off the stuff a "chosen one" has to do. Something makes your MC not say "Well @$&* this, I'm out" when things start going bad. What is that thing?
Have you ever considered the angle from people being ordinary. It just takes time patience and bravery to win. Imagine his step sister is the nutjob you describe, and he fights to defeat her. There is nothing special about him, but when it comes to it she cannot kill him. He is able to explain to her the wrong she has done, and in a moment of pure heartbreaking distress he has to end her rein of fear. She lets him. That is more powerful to me... but just thoughts to consider.
10 years old is a child. And, in the scenario that you describe, a traumatized one at that. Now, these protective powers, do they offer the child guidance and companionship? Or, do they act without him knowing they are there. How much of his destiny does he know? How much does he understand? You say he and his sister are living with a resistance group? Is this a terrorist group or a raider group? How much do they know about this kid? Even if they don't know of his true purpose, having someone around who can magically heal their casualties will be a big plus. Meanwhile, the sister with her 'kill stuff' power would be handy too. I can picture them growing up together, the sister becoming a harden combat vet while the little brother the see everything know everyone medic of the outfit. Godspeed!
