AN OKLAHOMA teenager convicted in the fatal stabbings of five family members is set for sentencing, when jurors will consider whether he should spend the rest of his life behind bars.

Michael Bever was 16 when he and his then-18-year-old brother, Robert Bever, killed their parents and three younger siblings in the Tulsa suburb of Broken Arrow, prosecutors said.

The older brother pleaded guilty in 2016 and a jury convicted Michael Bever of five counts of first-degree murder and one count of assault and battery with intent to kill.

The rampage started at about 11.30pm on July 22, 2015, when the boys started attacking their 13-year-old sister.

She testified that they lured her into a bedroom where they slit her throat and stabbed her in the torso and arms. Miraculously, she survived.

As they attacked her, their mother April, 44, came to the bedroom to find out what was going on.

They stabbed her nearly 50 times in the head, neck and torso.

Their dad, David, 52, was attacked next, stabbed 28 times.

Younger brother, Daniel, 12, was able to call 911 before succumbing to his nine stab wounds.

Victoria, five, was the youngest victim. Their two-year-old sister, Autumn, was asleep and not harmed during the attack.

“They punched a knife into their sister’s neck,” District Attorney Steve Kunzweiler said. “They then went and attacked their mum, gave her 40-some-odd wounds to her body. They then hunted down their dad and stabbed him in a bedroom. And then they had the audacity to go and knock on a door to try to lure out those children so they can stab them, so that they can go on some kind of cross-country crime spree.

“I want to know: When do you want them out? When do you want them as your next door neighbour?”

The jury will hear evidence from prosecutors and defence lawyers before recommending a sentence of life in prison, either with or without parole.

Defence lawyers argued that Michael Bever, now 19, was led astray by his older brother, and Robert Bever testified that he wanted to take responsibility for all of the killings. Robert Bever pleaded guilty in September 2016 and was sentenced to life in prison without parole.

The younger brother’s lawyer, Corbin Brewster, said after the verdict that he will urge the jury to sentence Michael Bever to life with the possibility of parole. He said his client was “stunned” by the verdict.

“The light at the end of the tunnel for Michael Bever is the most important thing that I can fight for at this point,” Mr Brewster said. “The jury has spoken. This is all we have left to fight for, for him. And we’re going to give it our best shot.”

But prosecutors said Michael Bever should be locked up for life because he was a willing participant in the gruesome killings of his family as well as the attack on a sister, now 16, who survived.

Mr Brewster argued that it was Robert Bever, not Michael Bever, who was behind the attack.

“What happened in that home was horrible. We don’t dispute that,” Mr Brewster said. “Michael Bever is honestly a gentle young man who was misled by a mentally ill older brother, and there’s a lot more layers to him as a human being than just what happened back in 2015.”