"How old are you?" Karen asked Manna.
"17, I just graduated from nursing school. And I know you're 15, so I'm older than you."
In Restylane, fifteen was the "age of adulthood". Generally speaking, if children didn't continue their studies after fifteen, they could work. For some children from less fortunate families, they might start working even earlier.
Although Restylane had laws prohibiting child labor (those under fifteen), the phenomenon of child labor continued.
In short, after Karen's awakening, he realized that this was a society with a huge wealth gap.
The gap was not only between the Immeras and Adams families but also between the real bottom class, who might have difficulty even feeding their families while running around daily.