the lesson gary is still learning from archie mcfarland. >> i still love my mother.n't harbor bitterness or resentment. there are tons of questions you'd love to ask and get answers to, but i'm not in a position, nor in my opinion anyone is in a position, to completely understand what's going on in somebody else's heart. >> that's all for this edition >>> i'm craig melvin. >> and i'm natalie morales. >> this is "dateline." >> all of a sudden, i realized, what's going on? something definitely was wrong. he said, your family was in an accident. and my whole world just dropped out from underneath me. >> the scene told the story. >> what did you find? >> something i don't want to see again. >> a deadly crash on a dark road, two gone, one barely alive.