Cortisol Response to Social Stress in Parentally Bereaved Youth Dietz LJ, Stoyak S, Melham N, Porta G, Matthews KA, Walker M, Brent, DA. The death of a parent is one of the most stressful events that a child can experience, and is associated with increased risk for psychiatric illness and impairment. Less is known about the effects of parental bereavement on physiological systems that initiate and regulate...