If I’m not mistaken, society used to be structured quite differently. Kids were not grouped so much by age in school, and with so much intermixing of ages in society, young kids were forced to grow up quite quickly.

For example, Alexander Hamilton began working full-time at the age of 11.

Nowadays, we try very hard to shield children from the realities of the world, sanitize their fairy tales, etc. but that’s a relatively recent practice.