By the age of five, Margo was certain that no adults on the planet were competent enough to care for her.
Both of her parents were well accomplished government scientists. They had loved her dearly, and were raising her to be very smart, but well adjusted girl. By the age of three, she was reading chapter books, even if they were short ones with pictures in them. A few months before her fourth birthday, she was even beginning to learn her times tables.
That was when her parents were called in to work on a top secret military project. No one could come with them, not even their own daughter. They dropped her off at a respectable looking girls' home and told her that they would be back in time for her birthday.
Margo's birthday came and went, but her parents never showed up. What did show up was a newspaper article depicting a massive explosion at a military base somewhere in the deserts of Nevada. Several of the best American minds perished in its wake. Margo recognized her parents' names among the list titled "Dead or Missing".
She kept that newspaper article with her at all times after that.
Several people tried to adopt her, but none of them realized just how precocious a smart child can seem. She was constantly asking questions about the natures of things, and questioning motives of seemingly insignificant things. Every parent that had adopted her ended up returning her within six months. This process continued all the way until she was nine. After that, everybody in town who was looking to adopt had heard the stories about the odd girl with the glasses who constantly questioned your judgment.