Son by Lois Lowry

From School Library Journal:

This final volume in the sequence of books that began with The Giver (Houghton Mifflin, 1993) returns for the first time to the regimented community of that book. Lowry recounts the events through the eyes of a new character, Claire, a Birthmother. When her first "Production" goes wrong, she endures a cesarean delivery and is summarily reassigned to the fish hatchery. But she can never let go of the idea of the son to whom she has given birth (Product #36) and manages to track him down in visits to the Nurturing Center. The baby turns out to be Gabe, the infant taken in by Jonas's family in The Giver. Claire meets Jonas's father and is able to maintain a tenuous relationship with her child. When Gabe is set to be "released" rather than permanently assigned to a family, things look dire indeed. Claire manages to escape the community on a supply boat headed "Elsewhere." Washed up on a beach after a storm, she has no memory of who she is or from whence she came. With the help of the villagers who have taken her in, she slowly regains some bits of her past and sets out to find her son. A harrowing encounter with the Trademaster leads her finally to Gabe, whom she finds in the village introduced in Messenger, along with Jonas, who is now appropriately the scholar/librarian of the community. Infinitely more satisfying than the previous installment, Son is a tender conclusion to this memorable story, and definitely the best of the books in this sequence since The Giver itself.