As a Tear Jerker page, all spoilers are left unmarked.
The Book:
The fate of families with 'illegal' children during the Delegation. Given the regimes strict One-Child-Policy combined with the Des Coin system, having a second child could mean the end of the entire family.
To fool the Insight implants parents could only ever interact with their second children while wearing a blindfold.
They also had to use all sorts of illegal means to receive an Insight implant for the child, putting themselves at the mercy of criminals and opportunists.
If the children were discovered they would be taken away from their families to be given up for adoption... if they were still very young that is. If they were already old enough to remember their parents, they would be killed just on the off chance they would grow up resenting the regime for it.
Even after the Delegation fell the tragedy of these children wasn't over, as the Triumvirate now returned them to their birth parents... tearing them away from the adopted parents they had grown close to, to live with birth parents they have never even known existed.
The story of Grace Ward in particular. She was discovered by Sonya just because she had briefly glanced out of the window of her home. When she is given the task to find Grace many years later Sonya hopes she can redeem herself for what she did. Only to find out that Grace was killed after being snitched out, by Sonya`s own father no less. When a remorseful Sonya reveals the truth to Grace`s family they won't even accept her apology.
As evil as the Delegation was, the rebellion that brought it down still killed many, many people including children and teenagers. Pretty much everyone inside the Aperture has lost most of their family during the uprising.
Some people like Nikhil and Mr. Nadir were betrayed by their own children, who sold out their parents to rebels to save themselves. We also hear of a case were a mother sold out her daughter to save her own skin.
Sonya lost her fiancée Aaron, who was killed during the initial riots and her best friend Tana, who was executed alongside her entire family for trying to flee the city. Her own family escaped into a hideout at first but when it was discovered by the rebels her father led the entire family to commit suicide, something only Sonya survived, being forced to watch her parents and older sister die right in front of her.
What makes it especially tragic is that Sonya notes that while her father and possibly her mother would have been executed by the rebels, having been locked in the Aperture alongside her sister Susanna would have left her with at least someone.
Speaking of Susanna, it is clear that while Sonya had some resentment towards her older sister by always considered the perfect daughter in the end her positive memories of her sister overwhelm the rivalry and she misses her sister dearly.
Alexander was actually the one who sold out Sonya`s family to the rebels. Something he does feel considerable guilt over, eventually driving him to ensure Sonya is given the chance to leave the Aperture. Little does he know that his higher ups have no real interest in going through with the promise.
Live in the Aperture, due to its sheer hopelessness. Especially for those being put there on account of being their parents’ children.
Many people fell into hedonism at the hopelessness of their life imprisonment. Drinking self-produced moonshine and overdosing on drugs, driving many inmates to an early grave. Others, including Sonya`s boyfriend David commit suicide out of desperation, not even leaving a note to explain why they did it... because everyone already knew.
Other people in the Aperture have gone into deep denial, trying to pretend that they have lost nothing, holding dinner parties and weddings as if they were still living in high society, while feeding of canned rations and wearing hand me down clothes. While the people in the Aperture were part of a tyrannical regime and are often unapologetic about its crimes it`s still sad to see how they have devolved.
When Sonya`s friend Nicole is released, some attention is drawn to her mother Winnie, while her daughter gets to be free it also means they will never be able to see each other again. Even worse Nicole will take on a new name in society, meaning that even the last connection between them will be severed.
At one point while with Emily Knocks Sonya almost breaks into tears when she is allowed to eat cheese toast and enjoy a hot chocolate. Simple things she enjoyed in her old life she never could have in the Aperture.
Emily Knocks death, while she comes off as a bit of a troll, her actions leading up to her death make it clear that she did genuinely want to help Sonya and was seeking the data on everyone’s Insight to delete it so no one would ever be able to abuse it ever again.
Sonya finding out the truth about Grace Ward. That she not only died because of Sonya`s snitching on her, but also her own father was the one who killed her. With the same poison he later used on his own family no less. Realizing that she will never be able to make up for ratting the young girl out nearly breaks Sonya. Even more so when Grace`s family outright refuses to accept her apology.
Sonya saying goodbye to her friends in the Aperture. While she can now finally leave the ghetto it serves as a reminder that for the others there is still no hope for a better future. Especially for her friend Renee who will now be the youngest person left.
