Among The Hidden by Margaret Peterson Haddix

In a dystopian society where families are restricted to having only two children, a third child named Luke lives in constant fear of being discovered by the Population Police. Confined to his family's attic, Luke's world changes when he meets another hidden child, Jen, who is determined to fight for their right to exist. As Luke grapples with the risks of stepping out of the shadows, he is drawn into a dangerous plan that could change the course of their lives forever, challenging the oppressive government that seeks to control them.

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