A Harris County jury sentenced a killer to death Friday for the execution of six members of the Stay family, including a husband and wife and their young children.

After stealing a firearm and gathering a laser sight and hundreds of rounds of ammunition, Ronald Lee Haskell drove from California to Texas in July 2014 to wipe out his ex-wife’s family, as he had always promised her he would.

The Stay family included Katie Stay,34, her husband, Stephen Stay, 39, and their children, Bryan, 13, Emily, 9, Rebecca, 7, and Zach,4, as well as the only survivor, Cassidy, who was 15 at the time.

“The death penalty is only for the worst of the worst,” Harris County District Attorney Kim Ogg said. “Haskell meticulously planned and carried out the slaughter of the Stay family and the death sentence handed down by a jury of his peers is appropriate.”

Melanie Lyon, victim Katie Stay’s sister, escaped an abusive marriage of a dozen years to Haskell before moving to the Spring area to be with her family several months before the murders.

After he got here, Haskell, now 39, spent two days stalking the Lyon and Stay families. He spent months planning the murder.

On July 9, 2014, he disguised himself as a FedEx delivery driver and made his way into the Stay home.

He held the children hostage at gunpoint until the parents arrived, forced them all to lie on the ground, and then shot them one-by-one.

Cassidy, the couple’s oldest child, was shot in the head, but survived by playing dead. Despite her injuries, she was able to assist law enforcement in capturing Haskell.

After the murderer left, Cassidy’s quick actions prevented Haskell from carrying out the remainder of his plan to kill 22 members of his ex-wife’s family. Cassidy delivered damning testimony against him during the trial, which began Aug. 26.

A jury rejected Haskell’s insanity defense Sept. 26 and found him guilty of capital murder.

Jurors then spent nearly two weeks listening to evidence about whether he deserved a death sentence or life in prison without parole.

“It has been an honor to represent the Stay and Lyon families through this difficult journey,” said Assistant District Attorney Kaylynn Williford, speaking on behalf of herself and fellow prosecutors Lauren Bard and Samantha Knecht. “We appreciate the time and attention the jury has given this difficult case in rendering a sentence of death. This has been a united effort of law enforcement, first responders, and the District Attorney’s Office to seek justice on behalf of the Stay family.”

The case marks the first instance in which the Ogg Administration has asked a jury to sentence a defendant to death.