Separation: The Underground 2

Twins, Ethan and Shawna, grew up in the underground mega-city of Complex 48 but now their worst nightmare is coming true - they are being separated. How will Shawna survive her debilitating "gift" and a stranger living in her home without Ethan's support? And how can Ethan help her from his new home in Complex 50?
Separation is the second book in the Underground series, the sequel to Complex 48. The Underground series is a middle grade science fiction adventure.