Showing Thursday's Child (Out of Time #5) by Monique Martin

The Crosses -- renowned Professor of the Occult Simon and irrepressible Elizabeth -- set off on their latest time traveling adventure. Leaving Jack behind to nurse his broken heart, the couple travels to 1852 Natchez, Mississippi to help the next person on grandfather Sebastian's list, Mary Stewart. There's just one problem. Little Mary Stewart, just 8 years old, died two days ago.

Mary's spirit cannot rest until Simon and Elizabeth solve the mystery of both her life and death. But Mary cannot speak, and there are those who are willing to kill to keep the past buried.

Simon and Elizabeth discover first-hand that dark secrets in the Antebellum South hide pasts murkier than the river bottom and twice as dangerous.