Isolation

Isolation is the seventh book in the Remnants series by K.A. Applegate.

Back Cover Summary
Three groups race to gain control of the ship and Mother, a computer that runs the ship and has been dictating the Remnants' every move. Mother is also the only chance the Remnants have to build a new Earth by harnessing her power to create environments. Billy knows Mother's true power firsthand, but now the baby is vying for control – and it may be indestructible.

The Remnants' conflict rushes toward something so finite, so unbelievable, weapons will be dropped, fighting will stop for a time...and new enemies will emerge.