In a chilling case, 17-year-old Mason Sisk has been convicted of capital murder for the execution-style killings of his father, stepmother, and three siblings in 2019. 

The Alabama boy committed the murders when he was 14 after discovering that his stepmother was not his biological mother. The jury took less than two hours to reach the guilty verdict, and Sisk now faces life in prison, the Daily Mail reports. 

Family Massacre Shocks Small Town

The murders occurred on September 2, 2019, in the small town of Elkmont, Alabama. Before the shootings, Sisk had tried to poison his stepmother by putting peanut butter in her coffee, knowing she was allergic. However, the poison attempt was unsuccessful. The subsequent massacre left the community in shock.

Sisk's attorney, Shay Golden, expressed disappointment with the outcome of the retrial, stating that relevant information was never fully considered.

Golden plans to appeal the verdict, believing a third trial may be necessary. Sisk's first trial was declared a mistrial, with the retrial beginning on April 17.

Unrepentant Killer: No Remorse for Brutal Murders

During the trial, prosecutors presented text messages in which Sisk bragged about using a gun to kill his family, claiming he could see the life drain from their eyes. The defense argued that these messages were meant as jokes.

On the night of the crimes, Sisk called 911 to report a shooting, initially telling deputies that he had been in the basement when he heard gunfire upstairs.

However, investigators say he later confessed to the murders and led officers to the murder weapon, a legally held 9mm pistol.

The victims were identified as Sisk's father, John Sisk, 38; his stepmother, Mary Sisk, 35; his two half-brothers, Grayson, 6, and Colson, 6 months, and his half-sister, Aurora, 5.

A 2020 report from a juvenile probation officer revealed that Sisk had not shown any sign of remorse for the crimes.

The document stated that 'Mason does not seem bothered by the fact he's accused of murdering his family... While in detention, he has not talked about his family at all.'

Troubled Past and a Tragic Revelation

According to Sisk's cousin, Daisy McCarty, the teenager's violent behavior was triggered by the revelation that Mary Sisk was not his biological mother.

“He didn't know any different of who his mom was. And they just recently told him, and I think that's really what triggered the little boy, to be honest with you," she said.

Before the murders, Sisk had displayed concerning behavior, such as burning live animals and breaking into his school.

Mary Sisk, originally from New Orleans, was a special education teacher for Huntsville City Schools. Evon Miller, whose granddaughter was in Mary's class, said, "I can't think of any better person to be with us during the time she was needed."

John Sisk held various jobs, including working at a Harley Davidson shop and graduating from a Paul Mitchell cosmetology school.

Sisk's sentencing is scheduled for July 25, where he faces life in prison for the brutal act that took the lives of his family members.