Transcript for Caseworker: Josh Powell Told Kids He Had Surprise
We're gonna turn out in the latest on the -- -- and we tragedy. When he twenties Chris Cuomo brings us an exclusive interview this morning. With the social worker who brought Josh Powell's two sons to his home and then frantically called for help after she smelled gas and realized something terrible was happening. Chris joins us now from Graham -- Washington good morning to you Chris. For -- -- -- it was supposed to be a supervised visit like so many before. Elizabeth Griffith -- driving little Charlie and Braden to see their father Josh Powell. The boys were so excited they ran up to the house but when that door opened everything changed. Did you did the door open did you see Josh I side just outside Josh street just 12 his eyes -- mind. And that any he had a look in his eyes and this just kind of sheepishly and then slammed the door as soon as the door close I heard him say. Charlie I've got a big surprise -- you. And then I heard Braden cry out and so I knocked denying not to name rang the doorbell and -- -- -- instead of yelling at Josh let me and it. Elizabeth is banging on the door when she suddenly catches the strong smell of gasoline. She rushes to call 911. And is shocked by the response. How Long Will it be I don't comment have to respond to emergency life threatening situation for the first available definitely open -- -- You're telling the 911 dispatch of this is that. This is emergency is a big deal of your kids and what are you getting from the other side. I'm getting how can you BEI. Could she supervisor of the -- -- -- -- -- -- -- -- -- Powell who can't have it -- says goodbye. Supervising -- with the defense I could provide health I'm not getting an emergency response and not responding to needs. At the level than I'm telling them connected -- the Catholic smelled the gas I told them. After 2911 calls and over ten minutes of questions Elizabeth is knocked back by a massive explosion as the house becomes a fireball. What did you tell yourself about how this could happen. Because Josh outlets really really evil and never sign any -- -- -- you know. Indicating it's from him he didn't look like for months -- he didn't look like somebody who is ridiculous children children Elizabeth says who were unique and talented. Kids she loved like her own -- an entirely what credible being. I'm Charlie with Smart and funny and -- loved black. Bugs and its and frogs. -- his favorite items like that -- to the boys like a piece of furniture to the boys they called bell over me. It shattered with me and that key they had -- -- tell me. While Elizabeth knows she is lucky to be alive she's in too much pain to appreciate that fact. What is the hardest thing for you deal with emotionally when you think about losing your voice. That they won't go up that they didn't see at this time in -- day. Jack can definitely have to look at but -- thing for this and kind that. That -- life hadn't stolen for them have been take that away. Elizabeth is dealing with tremendous guilt she feels he let the Cox family -- -- Josh I told her -- the Cox family told me. They take strength in the knowledge that she survived and they take solace in knowing that -- boys were with someone who love them. Before they entered that house Josh such perspective. And such strength thank you Chris and of course you'll have much more on the Powell -- tragedy on a very special 20/20 sins of the father tonight. 10:9 central on ABC rob all right.
This transcript has been automatically generated and may not be 100% accurate.