Jake Reiner, the elder son of Rob Reiner and Michele Singer, has published a moving Substack essay paying tribute to his late parents while also describing the “living nightmare” of losing them in December and his younger brother, Nick, being charged with first-degree murder for their deaths. “Nothing can prepare you for what it feels like to lose both parents instantly at the same time,” Reiner wrote in his lengthiest comments since issuing a joint statement with his sister Romy. “It’s too devastating to comprehend. I still wake up every morning having to convince myself that, no, it’s not a dream. This truly is my living nightmare.” He continued, “We lost more than half of our family that night in the most violent way imaginable. Sure, any loss of a parent is devastating, but nothing compares to losing both of them at the same time and, on top of that, having your brother be at the center of it. It’s almost too impossible to process.” “I understand that people have questions about what happened.…