Little murders in the maternity

Carla had dreamt of having children until everything changed: she would never be able to conceive. She finds herself devastated, assisting countless mothers in giving birth while knowing she can never experience it herself. A few months later, her husband is tasked with an investigation unfolding in the hospital where she works. Several murders of newborns have been reported. How can he conduct the investigation without upsetting his wife during interrogations while also protecting her? And what if they haven't seen the end of their surprises?