When your gifted and intelligent mother starts to get lost on drives around town, it's an indicator that things are going wrong.
Clare Avery-Allen began to realise her mother, Pamela, was suffering dementia-like symptoms about five years ago at just 56.
"She went and got diagnosed and they pretty much said they had been monitoring her for the past three years and it was really quite advanced," Ms Avery-Allen said.
"We really found it quite difficult at first but since mum has accepted it, it is a lot better."
Clare will undertake A Walk for Mum to raise money for Alzheimer's Australia with her sister, Kerri Anne Silburn, on the shores of Lake Burley Griffin on Sunday, November 2 from 11am.
"We thought how do we do something that means something to mum and also helps people identify early onset dementia and we thought a walk would be good," she said.
Before dementia struck, her mother was an exceptionally capable woman and raised two children single-handedly while undertaking Bachelor and Masters degrees.
During that time she rose through the ranks to become principal at Ourimbah Public School of 700 students.
"Mum was also a brilliant economist and had an eye for real estate," Clare said. "She bought many houses over the years, improved them and sold them for a profit."
Unfortunately, her mother now struggles to dress herself or to drive.
Ms Avery-Allen said raising awareness and money for Alzheimer's Australia helped her feel more in control of such a devastating diagnosis.
"I am hoping I can reach out to, and connect with, others who have been affected," she said. "I also want to promote the signs and symptoms of dementia, and encourage those who may suspect they or family and friends close to them may need help, to seek assistance as soon as possible.
"Though mum has finally accepted her diagnosis, she worries a lot about how her health is impacting our family. The grief that I have felt for her has, at times, been overwhelming."
There are more than 332,000 Australian living with dementia, according to Alzheimer's Australia.
This number is expected to increase by one third to 400,000 in less than 10 years.
Statistics show dementia is the third leading cause of death in Australia and there is no cure.
The walk raised $2200 of its $5000 target, at the time of going to print.
To donate visit https://give.everydayhero.com/au/awalkformum