I don't know which idea is sadder,
The idea that Poppy never found out that the Prototype is her brother, not understanding his pain, his perspective of their father and the torment that all started as a means to bring Poppy back. Not understanding why the betrayal he feels from her actions is so strong, not understanding why he obsseses over her and her choices and her feelings. Never knowing of what he suffered through, what he endured all because he was told that at the end of it he would have a family, he would have a sister. She will spend the rest of her eternal doll life mourning for the family she lost in life, mourning for any scrap of her family, pleading to stars she can not see for her father, to find any wisdom he may have left her, not knowing he left her an entire brother that doesn't reveal this knowledge because he doesn't think she will believe him and he can not tolerate the heartbreak of his sister's rejection. The idea that they both long for family but can not find it in each other because they have both become so twisted in their circumstances. And now the Player is here to kill the Prototype, Oliver, on Poppy's behalf without Poppy ever knowing the truth.
Or the idea that Poppy does know, that she had to watch her brother be twisted and corrupted by the awful place that took so much from their family. That she is forced to piece together who her brother was before the torture. That she knows she will never have peace with the one person who may be able to understand her grief. That she will never get to have a good relationship with the one member left of her family, of the one thing her father left behind. She gets to know that the one thing she wants most of all, family, is still alive and searching for her as well but it doesn't matter because neither of them will waver in their morals. Stuck on two different sides of a war, both just trying to find the best way to fix the mistakes their father made, both with very different perspectives of one man, neither understanding that the version of their father the other had was different than their own. Poppy has to make the difficult choice to enlist the Player to murder her own brother, and insisting to herself that it is the only way. That killing the only remaining member of her family is worth it for the cause.
