I used to do something similar with my fingers – each hand was a family, with thumb = little brother, index finger = mum, middle finger = dad, ring finger = big sister, pinkie = little sister. The right-hand family used to bully the left-hand family, because they were cleverer and more capable. I have all their names written down somewhere.
My 7-yr-old gets similar anxieties at bedtime, although God is not in the equation. We generally find that various forms of distraction work best to calm him down.