After losing hundreds of dollars on the pokies, Hanny Papanicolaou climbed the back fence of Marjorie Welsh's home where she attacked the vulnerable 92-year-old on January 2, 2019.

The 39-year-old gambler, whose guilty plea to manslaughter was rejected by the Crown, was found guilty of murder by a NSW Supreme Court jury in February.

Ms Welsh died in hospital six weeks after being bashed and stabbed in her inner west Sydney home.

Justice Robertson Wright on Friday jailed Papanicolaou for 22 years with a non-parole period of 15 years.

"I am satisfied on all the evidence that the murder was unplanned and impulsive," he said.

He found Papanicolaou had gone to the house with the intention of stealing from her employer, but later developed an intention to kill her.

Ms Welsh gave two police interviews when in hospital, naming her assailant as "Hanny the housekeeper" and describing the "utterly ferocious" attack in detail.

When asked if she could think of a reason for the attack, she replied: "It would be a peace of mind if I could.

"There are usually logical reasons for things that happen in this world, but I cannot see any logic in this."

The judge found Papanicolaou was not suffering from a major depressive illness at the time, but did have some symptoms of depression and anxiety.

"The death was a great human tragedy especially for her family and for all others affected by this sad matter," he said.

Angela MacLeod, one of her two daughters, previously said their mother was someone who could achieve anything she wanted in life.

"Life wasn't always perfect for mum ... but she was strong, intelligent, loving, protective, all those things that you'd want in a mum. We were always very proud of her," she said.

The judge said she was taken from her daughters and families in a way they found was unthinkable and inexplicable.

Australian Associated Press