A forensic psychiatrist testifying for the defense told the Oscar Pistorius murder trial on Monday that the double amputee track star suffered from an “anxiety disorder” after growing up with a mostly absent father and a mother so afraid of intruders that she slept with a firearm under her pillow. The testimony by the psychiatrist, Merryll Vorster, offered an uneasy echo of Mr. Pistorius’s own account of events in his bedroom in the early hours of Feb. 14, 2013, when he has admitted taking a handgun...