Ms Southern, 35, lost her mother and primary carer Dorothy to brain cancer on Tuesday.

A day earlier she was due to be relocated from Dapto to a group home at Queanbeyan because a place could not be found for her in the Illawarra.

It was after first viewing the home on November 19 that the bald spot on Ms Southern's head started to appear.

Her sister Jane Southern, 43, fears that if forced to move to Queanbeyan the change in routine, already in motion by their mother's death, will destroy Kate.

"This is all she's ever known, her family and the Illawarra," Ms Southern said.

An appeal to the Department of Ageing Disability and Homecare has been to no avail.

"The department has told us there is a four-year wait for a home in the region and that unless we take the home in Queanbeyan, we'll miss out," Ms Southern said.

When Dorothy Southern, 70, was diagnosed with brain cancer in March, the Disability Trust provided a nurse from 7.30pm to 7.30am daily for Kate, who requires around-the-clock supervision.

Home Care was brought in to assist with her morning shower before she attends a day care group at West Dapto, organised by the House With No Steps.

"She can't wait to get to day care and doesn't want to leave. Her friends are there," Ms Southern said.

"Belly dancing is her favourite - you should see her. She will lose all of this if she's forced to leave."

Ms Southern, a mother of three, now has primary care of Kate while sister Jenny, a single mother of four from Oak Flats, assists.

"We asked for a group home placement when mum got sick. Two group home placings came up in the Illawarra, but we were knocked back.

"Then they said, 'you can view Queanbeyan'. So we viewed Queanbeyan.

"Kate was immediately distressed. People with autism need to have a stable routine.

"Since last Wednesday, she's had a big bald spot on the top of her head. She's pulling out her hair because she's so frightened."

The family's distress increased with notification the in-home respite funding through the Disability Trust would cease on December 22.

Ms Southern approached Member for Shellharbour Lylea McMahon, who made an urgent appeal on the family's behalf to Minister for Ageing Disability and Homecare Paul Lynch.

A spokesman for Mr Lynch said Ms McMahon's letter was received on Wednesday and the minister had not had the chance to address it.

"The department will continue to work with the family to sort out the issue," he advised.