Widow Kang is Book 6 of the novel The Years Of Rice And Salt.
Summary
Widow Kang Tongbi feels a deep connection with wandering Buddhist monk Bao Ssu; when her son Shih falls victim to soul theft, Bao is unjustly accused and tortured to death, and Kang is sleepwalking.
Ibrahim ibn Hasam, Muslim schloar, comes to investigate. A deep bond is created between Ibrahim and Kang. Together they go through hypnotism sessions that allow them to remember their past lives together.