she was at her boyfriend's jonah shacknai's house with her young sister zena and shacknai's son max.on max. >> rebecca is in the house with her little sister and max is on the floor playing. and suddenly something happened. >> zena called 911. >> he fell down the stairs, he's not breathing. >> max took a horrific fall which neither rebecca nor zena saw. rebecca called jonah. >> i sprinted into the house and saw max playing on the floor. did he tell you how it happened. >> said i really don't know. >> jonah held vigil by max's hospital bedside and next day his brother adam flew in from tennessee. >> adam was in the guest house. rebecca was at home, they were the only two in the house. >> they were exceedingly cordial both good people. >> early on the that morning july 13th adam says walked into something unimaginable. >> he saw her body hanging from the balcony and he called 911. >> i got a girl hung herself. >> is she still alive. >> i don't know. are you alive? no. >> adam told investigators he cut rebecca's body down and tried to resuscitate her but already too late, rebecca zahau

in damages. >> hopefully people will know that she didn't commit suicide. >> reporter: adam shacknaifrom tennessee was visiting his brother at the time of rebecca's death because of another tragic mystery which occurred inside the beachside mansion. his brother's 6-year-old son max plunged over a second floor railing and was hospitalized. he later died. rebecca was the only adult home at the time. days later adam found rebecca's lifeless body bound and gagged and cut her down and called 911. >> 911 emergency, what are you reporting? >> yeah, i got a girl hung herself. >> okay. is she still alive? >> i don't think so. >> reporter: the case was eventually ruled a suicide but rebecca's family never buying it suing adam shacknai in civil court. adam's brother jonah defending his innocence in an exclusive interview with abc news. >> he wakes up and his life is changed forever, not because of anything he did, but just because of where he was. >>> and we're now joined by sunny and dan abrams. surprised by the verdict? >> not surprised. remember, this is a california -- civil case so the bur