At first when they opened the door they didn't see Herbert at first. Then Mr white had opened the door again because he heard knocking. As he did Herbert was their and was all chopped up and scary. When he look he didn't see Herbert.
after Mr White didn't see Herbert the first time he left. Then he was still hearing knocking so he went back to the door. He saw Herbert and Herbert killed him as soon as they looked at each other.
Once Herbert kills Mr White. Mrs White comes running to the door because she hears screaming. once she gets their Herbert kills her to. Then after he kills them he was all depressed because he didn't now what he was doing he thought it his dad's fault that he died.