I had my Walking Dead Rp set 14 years after the fall of the old world destroyed by someone I thought I could trust and even made one of the two co-storytellers; they never read or decided that it didn't matter that I'd put in the rules all PC were to be between 18 and 25 years old. They decided they had someone in their unit that was 15 and panicked in a battle scene.
We were a new military group from a town made by survivors and their children or children that had survived the fall trained by the old military men that had lived in the area; I did that so I wasn't over run by Spec-ops types because like the real military the older ones train and the younger ones do.
Stick to your vision, you are like the creator/producer of a TV series and though we the writing staff whine and complain in the end you set up the story board
@Jasper19