In Caroline B. Cooney's The Face on the Milk Carton, sixteen-year-old Janie Johnson sees a photo of three-year-old Jennie Spring on a milk carton and immediately notices a similarity between the child and herself. The caption under Jennie's picture indicates that she was kidnapped some thirteen years earlier. In addition to a physical resemblance, Janie also believes she remembers the dress Jennie wears in the photo and begins to wonder whether she is the kidnapped child. When she finds the dress in the attic and her parents will not provide her birth certificate, she concludes that she is, indeed, Jennie and that the loving parents who spend much of their time giving back to the community stole her from her biological family years before.
This causes Janie to question everything about her life and her parents. How can they be good people if they kidnapped her? Yet, they have always seemed to be moral and upright. Moreover, this crisis occurs at a time when many young adults question their identities and wonder about the kind of adult they want to become. In the passages leading up to Janie's discovery, she has even changed the spelling of her name to appear more interesting.
Over the course of the novel, Janie examines all of the facts, does some research and eventually concludes that she is Jennie. Not surprisingly, this causes her to view her family, her friends, and the world around her through a cynical lens. Throughout her early childhood, her parents represented the good in the world, and now she believes that they are kidnappers. Thus, she wonders, how can there truly be any good in the world?
Things begin to turn around after she opens up about this dilemma, first to Reeve, the boy next door, and then eventually to her parents. In a painful and emotional scene, they explain to her that they once had a daughter named Hannah who ran away to join a cult. Years later, Hannah returned with Janie, and they believed Janie was their granddaughter. They took Janie—or Jennie—in and broke all ties to Hannah in order to raise the girl as their own daughter.
This restores Janie's belief in her parents' morality and goodness. In chapter 15, the author writes,
Peace settled in on Janie. She felt heavier, as if her weight might press on Reeve until his ribs broke. She said, "Mother and Daddy aren't bad then."
"Well we don't know anything for sure. But that way, your parents' story is entirely true. Lizzie and I can't believe they would have been part of anything criminal or evil."
"Hannah was the evil criminal." Janie was so lethargic she could not imagine moving again....
"I don't know," said Reeve. "I don't think Hannah sounds evil or criminal. I think she sounds like a scared, cult-blinded automaton."
By the end of the book, Janie has come to realize that her parents truly believed that she was their granddaughter and had done nothing immoral. When she tells them about the kidnapping and that they are not actually related to one another, their horror at the unknowing role they played in keeping a child from her "real" family is palpable. They understand the pain the Spring family must have felt and probably still feel.
"In their place," said Janie's father, "I'd move heaven and earth to ruin the people responsible."
Janie's mother makes the decision to contact the Springs and let them know that their daughter, missing for over a decade, is alive and well. This act restores Janie's belief in their goodness and in the general possibility of goodness in the world.