The orphan ship
(Book)

Stranded 225 million kilometers from home on Mars Station, cousins Jake O'Brien and Lorina Murphy are drawn into a fledgling effort to help the hundreds of abandoned street children who call the station home. Jake becomes a medical apprentice in an outreach clinic, while Lorina volunteers at a juvenile shelter. They soon discover that their efforts may be in vain because something much more serious than poverty plagues Mars Station. Also stranded on Mars Station, ship's captain Danae Shepherd faces the difficult task of hiring replacement crew after an alien virus claims the lives of four in her employ, including her husband. She stumbles upon the same problem that has Jake and Lorina stumped: why are homeless children disappearing without a trace?