surround him, and the grave scene unfolds. when robert stops moving, paramedics are called. he's pronounced dead at the scene. >> they say, i have very bad news for you. your son died. then i went in shock. i was crying. i was asking why. >> an initial autopsy finds no trace of alcohol, drugs, or disease, but fails to find a specific cause of death. >> he was not a sickly person. wasn't a diabetic, for example, or a person that required any kind of regular medication. >> the video is voluntarily handed over to police.