Street Dreams (Decker/Lazarus Book 15) by Faye Kellerman

Detective Peter Decker teams up with his wife and daughter to solve a crime rooted in both the past and present. While on routine patrol, LAPD Officer Cindy Decker rescues a newborn abandoned in an alley dumpster. But she can't call it a night until she sees the infant safe in a hospital, cared for by a professional -- in this case a male nurse with soulful eyes and lots of charm. Now the hunt is on for the mother. Armed with advice from her overworked father, Detective Peter Decker, Cindy plunges into her inner-city Hollywood district, a world of helpless people and violent gangs. Pursuing each new lead batters her complex relationships and endangers her life. On one side: Decker and Decker, a brilliant but combative pair. On the other: a vicious killer ready to strike again. While on routine patrol, LAPD officer Cindy Decker rescues a newborn abandoned in an alley dumpster. Cindy searches for the mother in inner -city Hollywood, following a treacherous trail filled with drug lords. But with each new lead, the twisted journey gets darker -- and endangering her very life. When Decker and Decker join forces, can this edgy duo put personal issues aside to catch a vicious culprit before he strikes again?