. >> three years after viviana's death, her older sister, stella tulli, visits her grave site regularlyhe fact that the murder was committed on their mother's birthday. >> you know, we all have a birthday. that's our own special day, the one day we get to celebrate for ourselves. he even took that away from my mother. not only did he take her youngest daughter, he took the one day she had for herself. one of the first questions i thought that night before bed is did he strangle her from behind and she couldn't fend him off that well, or was he looking in her eyes? what was she thinking as he was taking the last bit of breath from her? >> neither stella nor the rest of the family knew much about goodell's account of the murder, including the fact that he was facing viviana when he strangled her. at stella's request, our producer provided her information about this and other revelations made by goodell, but there are other questions no one can ever answer. >> i just think about, what were her final thoughts? like am i going to die? i'm never going to see mommy again. a lot of thoughts tha