Diana Orgain. Motherhood is Murder (2010) 307 pp. [pbo]
Publishers description: Nights out are hard to come by for new parents. So when Kates new-mommy club, Roo & You, holds a dinner cruise, she and her husband, Jim, leave baby Laurie with Kates mom and join the grown-ups for some fine dining on the San Francisco Bay. But when one of the co-founders of Roo & You takes a fatal spill down a staircase, the police department crashes the party. Suddenly every guest is a suspect, and it seems like every mom and her man has a motive. Kates on deck to solve the mystery—but a killers determined to make her rue the day she joined the first-time-moms club...
Setting: San Francisco; San Francisco Bay (shipboard)