Rule 20

The year is 2152. The United Empire has just finished celebrating it's 20th year celebration of surviving the event that has been dubbed "The End" in the History books. Fifty years ago humanity took a turn for the worst. Countries were at each others throats to try and gain resources. Overpopulation had driven people to war and violence. That is until the United Empire came up with Rule 20. Not just Rule 20, but a list of Rules to keep people in order. Rule 20 specifically limited people to two children. One boy and one girl. That is it. If anyone was found breaking this rule, they would face capitol punishment.
This may be the case, but where there are rules, there are rule breakers. People who decide to say screw the law, but also people who decide later on that they want to replace one of their children with a "better" one. Children could still be born and given away at birth or even up to the age of ten. These children were sent far underground. The unwanted and unneeded children were sent to factories where they were provided only what they needed to survive. Once these children were old enough to move around on their own and able to work with their hands, they were put to work in these factories. Escape from which was impossible. Even if someone was able to escape, children were branded with tattoos on their ankles at birth. From these people could see that they didn't belong in the outside world and they would be "dealt with" once found.
Of course the situation was great for those able to live above ground with these new rules in place. Overpopulation was cut down tenfold and nature was returning back to a healthy state. People like Rose Witherfield were very unhappy with these rules. She was assigned to work at the Chemical factory and was given a tattoo on the inside of her ankle with CH23 on it.
Let the count down begin till her escape.