Oracle. Coven, #7

It's better not to know things sometimes. Suspecting she might be pregnant, Samantha seeks out Vanita, an oracle, to ask whether she and Steven are even ready to have kids. During the reading, Samantha receives a vision of a man bleeding out on the ground. Learning from past mistakes, Samantha recruits Kathy's help to track him down. After searching for hours in the frigid winter night, the sisters come up empty.
Samantha returns to Vanita for further answers and learns that the man in the vision is none other than Vanita's brother, Oren. When the sisters enact their plan to save Oren, they discover that Vanita isn't as innocent as she let on. Right in front of the sisters' eyes, she stabs her brother and steals her family's powerful amulet to wreak havoc with it. The sisters are ready to launch into a search for Vanita, but must tend to Oren's physical injuries, as well as some of their own intangible ones as Kathy finds Steven in a compromising situation, which erupts in the biggest marital spat he and Samantha have ever had.
The sisters must pull together their emotions and trust each other if they're going to get the amulet back. Otherwise, the world as they know it could be over. Oracle is the seventh book in the Coven series, which serves as a prequel to the Under the Moon series.