Did Robert Jr. have help?

The parents were attacked while they lay in bed. Mr. DeFeo, however, was able to struggle to his feet to attempt a counterattack on his assassins. A second bullet struck him dead before he was able to reach his target. Louise DeFeo lay in bed, moaning for help, as she slowly bled to death. A second bullet would silence the woman for good.

Although the original plan called for the younger children to be taken to the grandparents' house in Brooklyn, Dawn, according to Butch, killed them to eliminate the children as witnesses and potential threats. Butch claimed he was not in the house at the time of the children's murders, but giving pursuit to one his friends, who had fled the scene, in order to lure him back to assist with the cleanup. Even while feigning insanity at trial, Butch DeFeo never admitted shooting the children.

One can only imagine the horror on Marc's and John's faces when their big sister entered their room with a rifle. Dawn callously ordered the boys face down. A clue that the DeFeos were awake at the time of the murders rested in the final position of Marc DeFeo's body. Because Marc had suffered a debilitating injury from football, he was forced to sleep on his back. Yet, he was shot face down in bed. The prosecutor confirmed this fact at the DeFeo trial.

The next room Dawn entered was Allison's. Standing at the doorway, Dawn raised the rifle, taking aim as Allison slightly raised her head before looking into the muzzle flash. Death was instantaneous, as the bullet impacted Allison's left cheek and exited her right ear. Allison's wounds were meant to disfigure the beautiful girl.

Butch, upon his return and enraged at the senseless murder, confronted Dawn DeFeo in her third-floor bedroom. After briefly wrestling for the gun, Butch got the upper hand and slammed Dawn against the bed knocking her out. As she lie unconscious on her bed, Butch placed the back of the rifle to Dawn's head and fired. 

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