Why do mums kill their children?

A memorial vigil is held for Adam Williams at the Civic Park gazebo in Walnut Creek on July 26, 2009. His mother, Judith Williams, of Walnut Creek, reportedly took her 16-year-old son's life before taking her own on Mount Diablo, according to sheriff's investigators. (Cindi Christie/Bay Area News Group/MCT)

IN Raijon Daniels’ short eight years of life, his Richmond mother, Teresa Moses, beat, starved and washed him with household chemicals and high-pressure hoses.

In 2009, Judith Williams drove her 16-year-old son to the top of Mount Diablo State Park, shot him in the back and head, and then turned the .357 revolver on herself.