2012’s What’s Left of Me is the first volume in Kat Zhang’s Hybrid Chronicles.
Alone of all the world’s regions, only the Americas have chosen to eliminate the two-minded adult hybrids, to seal themselves off from the chaos that hybrids cause. The rest of the world can have its Great Wars, but North and South America are secure, peaceful, and steadfastly conventional.
Like all human children everywhere, Eva and Addie were born as hybrids, two minds sharing a single body. Most New World children settle, a process in which the weaker of the two minds fades away, leaving only a single, stable, intellect. Although clearly fated to vanish, Eva lingered on, unable to control the shared body, but still present. Despite the best treatments modern medicine could offer, it seemed the child was doomed to be one of those unfortunates safely sequestered away from decent folk.
Eva_and_Addie eluded institutionalization by embracing the one technique that would keep the adults satisfied. They lied.