No. The stepfather killed her sister, you can see because her shot ends up in the tube thing-y. That's why that whole scene was planted together that way. Too lazy to elaborate; but that makes Babydoll completely weak and nixes the entire story even if it would have been accidental. By the time she arrived, her sister was already dead. If she had shot her, the bullet hole would have been further down. Also, the light wouldn't have been hit. And the thing did explode over her, but it was just small glass pieces and she didn't get electrocuted because her head was bleeding.