House of Suns (GollanczF.)

Abigail Gentian fractured herself into a thousand male and female clones. Sent out into the galaxy, they meet every two hundred thousand years, to exchange news and memories of their travels with their siblings. Campion and Purslane are late for their thirty-second reunion, and they get more than the scolding they expect. They face the discovery that someone has a very serious grudge against the Gentian line, and there is a very real possibility of traitors in their midst. The surviving shatterlings have to dodge exotic weapons while they regroup to try to solve the mystery of who is persecuting them, and why.