Norfolk, Va,. - At a family Christmas party back during the winter, 84-year-old James Johnson showed his grandson several Christmas cards he had received.
The cards contained money.
Johnson's grandson, Tauris Sills, "took notice" of the cash.
Days later, Tauris went to his grandpa's house, pushed him down, then kicked him in the head over and over again.
Then he searched the home for money.
Back when it happened, Tauris spoke to NewsChannel from jail. He says he blacked out.
Johnson's family went over to the home and found the elderly man lying in a pool of blood, and several bloody footprints.
Three days later, Johnson died of blunt force trauma to his head.
Tauris was charged with his murder and in his mugshot, he has black eye.
He pleaded guilty to the crime this week.
Court documents say Tauris' family told police he had recently been released from jail, was back using drugs and had stolen a car from his cousin.
Tauris admitted to police he was high when he beat up his grandpa.
“I don’t understand it myself. How could I do it? I think about it every night,” says Tauris.
Months ago -- Stills says he suffers from PTSD, bipolar disorder, anxiety -- and he hears voices.
Sills will be sentenced in September.