Corey James Lovell and his mother Samantha Ann Brownlow are accused of murdering Robin Behrendorff in his Burnett Heads home in 2011.

Corey James Lovell and his mother Samantha Ann Brownlow are accused of murdering Robin Behrendorff in his Burnett Heads home in 2011. contributed

A MOTHER and son have each been sentenced to life in jail for the chilling and brutal murder of the woman's stepfather in a fumbled attempt to claim an inheritance.

Samantha Ann Brownlow, 45, and her son Corey James Lovell, 21, snuck into Robin Behrendorff's Burnett Heads home in April 2011 where they viciously bludgeoned and stabbed him to death, leaving him to die alone in a pool of his own blood.

Brownlow pleaded guilty to the murder while her son Lovell pleaded not guilty, leading to a six-day trial in Bundaberg Supreme Court.

But the jury was not convinced of his plea - finding him guilty after deliberating for less than an hour.

Lovell buried his head in his hands and began to cry as the jury delivered their verdict.

When his mother was brought into the docks to be sentenced along with him, she placed a comforting hand on his shoulder but he was quick to push her away, causing the police guards to move her to a seat out of his reach.

It is beyond the comprehension of most of us. What you did was simply evil.

Crown prosecutor Greg Cummings said Brownlow was the one who planned the murder and after a failed attempt to recruit her own 15-year-old daughter to help her, turned to her son Lovell who was the "brawn".

"Brownlow was the driving force behind it all," Mr Cummings said of the woman.

The court was told Brownlow believed she would inherit $500,000 from Behrendorff, $50,000 of which she promised to her son to help her, but had no idea he had changed his will to leave her nothing at all.

It was revealed the Behrendorff had been kind to his stepdaughter, allowing her to live with him for a time in 2010.

In a sadly ironic twist, he had also bought her the car that she ended up using to travel the almost 1000km round trip from Toowoomba to Burnett Heads in order to murder him.

"Brownlow must take the bulk of the responsibility for the plan and Lovell for the execution," Mr Cummings said.

"It is a chilling example of someone who decides to kill for money.

"Brownlow's involvement is of course horribly chilling."

Justice Duncan McMeekin said the violence inflicted on the older man was "substantial".

"It's chilling," he said.

"It is beyond the comprehension of most of us.

"What you did was simply evil."

Lovell's lips trembled as his mother was first sentenced to life in prison and he continued to cry as his own fate of life imprisonment was handed down.

"In my view the evidence was overwhelming," Justice McMeekin said.

"The most that can be said of you is you came under the influence of an evil person," he told Lovell.

"The facts are chilling. It is almost beyond belief that you would do such a thing."