Brittney Jade Dwyer, 19, pleads guilty to murder of her grandfather Robert Whitwell at Craigmore

• Robert Whitwell’s granddaughter told friend he ‘might have to die’
• How a seemingly nondescript death became a murder investigation

A YOUNG Queensland woman has admitted murdering her grandfather inside his Adelaide home, just a day after a court heard how she had told a friend not to get attached to him because he “might have to die”.

Brittney Jade Dwyer, 19, made a brief appearance in the Adelaide Magistrates Court on Tuesday by video link, during which she pleaded guilty to the murder of Robert Whitwell, 81, at Craigmore in August.

The hearing came only about 24 hours after a court heard that Dwyer and her friend, Shelby Lee Angie Holmes, 19, had watched Mr Whitwell for several days as they planned to rob him of $30,000 in May.

The pair and a third woman, Bernadette Burns, were arrested by Major Crime detectives who investigated the “unexplained’’ death of Mr Whitwell after his body was found inside his house on August 8.

Dwyer and Burns, of Redbank Plains, about 30km southwest of Brisbane, were extradited to Adelaide earlier this month to face charges of murder while Holmes was arrested last week in Queensland and charged with aggravated serious criminal trespass.

Holmes, 19, of Ormeau in Queensland, appeared in the Adelaide Magistrates Court on Monday for a bail application.

The court heard that she was warned by Dwyer not to get attached to Mr Whitwell because “he might have to die”.

During Holmes’ extradition hearing last week, a Queensland magistrate said the prosecution case against her suggested she was involved in a “premeditated calculation” to steal from Mr Whitwell.

He said it appeared that crime had been agreed upon with an “an element of indifference” as to how it would be achieved — a mindset that “does not provide me comfort”.

During Holmes’ appearance on Monday, prosecutors alleged that, on April 30, she and Dwyer drove from Queensland to Craigmore to “observe” Mr Whitwell.

They claimed Holmes sent Dwyer a text message saying “he said ‘hi’ to me, he’s lovely” to which Dwyer replied “don’t get attached to him, he might have to die”.

Prosecutors said those messages were part of 19,000 texts sent between the pair over two years that had been recovered by investigators.

Dwyer has been remanded in custody to appear in the Supreme Court at a later date.

Holmes and Burns are yet to enter pleas to their respective charges and have been remanded in custody to face court again at a later date.

The investigation into Mr Whitwell’s death began after neighbours became concerned when they noticed a newspaper lying uncollected in Mr Whitwell’s driveway.

One told The Advertiser said he had seen Dwyer outside Mr Whitwell’s house about four days after he was found dead. He said Dwyer did not seem distressed.

“She was on her phone, sitting in the gutter outside the home,” he said.

“I’m still scratching my head wondering what happened in there and why.”

Other neighbours said Mr Whitwell made daily visits to his wife, who suffers from dementia and lives in a nearby nursing home.