A woman with multiple sclerosis who died at home from malnutrition and sepsis weighing just 30 kilograms had slipped through the gaps of the health system, an inquiry has been told.

The Royal Commission into Violence, Abuse, Neglect and Exploitation of People with Disability is this week examining the experiences of women and girls with disability.

Margaret Burn's sister-in-law died aged 48 in March 2007, after being diagnosed with the neurological disease eight years earlier.

The commission was told a coronial investigation determined her cause of death was malnutrition and sepsis from untreated bed sores.

Ms Burn indicated she found out after her sister-in-law's death that she had been admitted to hospital in October 2006, potentially in a "state of starvation".

"None of the family even knew that she had been admitted to the hospital," Ms Burn said.

A registered nurse, Ms Burn said she reviewed her sister-in-law's medical record.

"She was semi-conscious. They said she looked as if she ... had lost a considerable amount of weight which she couldn't afford to lose," she said.

"After four or five days of nutrition she became conscious."

Ms Burn's sister-in-law returned home to her husband, who was later convicted of manslaughter over her death.

Counsel assisting the royal commission, Kate Eastman SC, asked whether Ms Burn felt the hospital overlooked the seriousness of her sister-in-law's condition.

"Yes. She was end-stage (multiple sclerosis). She was terminally ill," she said.

"I have never been able to understand the reasoning (for her returning home)."

Ms Burn agreed her sister-in-law had gone unnoticed by the health system.

"And slipping between the gaps put her in that situation of danger and not having the support she needed," she said.

"She couldn't advocate for herself, because if she had ... she could have advocated very well for herself."

Ms Burn's sister-in-law had worked as a nurse, including in aged care, before her multiple sclerosis progressed.

The commission was told Ms Burn's sister-in-law's husband was also a registered nurse and had depression and other mental health issues.

Ms Burn's sister-in-law had previously spent seven months in hospital after police found her in a "state of neglect" at home.

Ms Burn said her sister-in-law was someone who would light up a room with her smile.

"Although she was a country girl, she had a real style. (She) always was just passionate about her life and everything that she took on," she said.

The royal commission has previously been told roughly 48 per cent of women with a disability will experience physical violence, compared to 27 per cent of women without disability.