There were day-to-day costs Hayley covered using the stolen money too; clothing, groceries and child-care expenses.
And it was no simple fraud.
Hayley broke several term deposits, incurring bank fees, and would then make a series of "complex transactions" through various accounts before transferring the money to herself in small amounts.
Karen was ripped off nearly $85,000 with $15,000 in fees and lost interest, the court heard.
Defence counsel Sarah Saunderson-Warner said her client had since sold her home to raise the $101,640 owed and was now living in a rental property in Roxburgh village.
While the facts of Hayley's offending were damning, her victim spoke tearfully of the human cost of the ordeal.
"I feel ripped off," Karen said.
"I don't want to know Hayley. I never want to see her again, she is no sister of mine.
"She never treated me like a human being."
Karen spent the first 18 months of her life in hospital with a rare condition which resulted in brain damage.
Karen hated school and only found joy when she began work as a dishwasher.
Her earnings exceeded her scant spending and as the years passed, her savings mounted.
That was until 2012, when Hayley became involved in managing the victim's finances.
Karen said her sister would call her "*** thick" and "*** useless", while keeping a strangle-hold on her cash flow.
The stress, the victim said, caused her to become physically unwell but when she asked Hayley to pay for a doctor's visit there was no sympathy.
"You can't afford it, take a *** Panadol," Hayley had said.
Karen also said the defendant would force her to babysit her children, sometimes without any warning.
The personal jibes grew during the last year of Hayley's reign, she said.
The defendant annotated the victim's bank statements with comments such as: "whinger food top up" and "food for fatty".
"That really hurt when I read those.
"She made me feel unwanted, unloved and miserable. In the end I was just really, really sad. I didn't have much of a life," Karen said.
She paid tribute to Detective Sergeant Derek Shaw who had spent the past two years on the case and the friends who had stood by her throughout.
Judge Phillips called the offending "serious thieving".
"The offending was calculated, premeditated, repeated and it was all against her sister who she was aware was entirely disadvantaged," Judge Phillips told the court.
The fact Hayley had repaid the six-figure sum was all that saved her from a term of imprisonment, the judge said.
She was sentenced to five months' community detention (on a 7pm-7am curfew daily) and 200 hours community work.
Judge Phillips also ordered she pay her sister $5000, for emotional harm, by the end of January 2019.
