It was while on holiday on the NSW south coast that Royce Simmons realised something wasn't right.
The former rugby league player's memory had deteriorated despite him only being 61-years-old.
"My wife was actually getting a carton of beer out of the back of the car and I asked 'where did you get that from?' and she said 'we just pulled into the hotel and you watched me get it'," Mr Simmons said.
"I couldn't remember that, I thought she was joking."
The former Penrith Panthers premiership winner decided to see a specialist.
"I was expecting him to say 'you have some slight problems here, some slight problems there'," he said.
He said sitting down with his wife and then bringing his kids and grandkids together to tell them he wouldn't know who they were in a few years was not a very pleasant thing to do.
Mr Simmons began a 300km walk from his hometown of Gooloogong in the New South Wales Central West to Penrith Stadium on Tuesday to raise money for Dementia Australia.
He said the idea was inspired by the charity work of former rugby league player Mark Hughes.
"I thought I might raise $50,000 to give to research for Dementia Australia but all of a sudden this got bigger and bigger."
Mr Simmons is now hoping to raise $500,000 across his 11 days of walking.
Trying to slow it down
Almost half a million people are are living with the illness and it is the nation's second leading cause of death, according to Dementia Australia.
Mr Simmons said he had been diagnosed with dementia "reasonably young" and was trying to reduce its effects.
"I am just trying to do everything in my power to slow that up, so I exercise anywhere between three and six hours per day, I am on medication, I do different quizzes."
'We will go with him'
Mr Simmons will be joined by sporting legends such as Wally Lewis, Kurt Fearnley, Allan Langer and Terry Lamb on his walk.
Former teammate and NSW Blues coach Brad Fittler said he was not surprised by how Mr Simmons reacted to the diagnosis.
"I was always confident that he wouldn't just sit there and end up in an armchair watching TV," he said.
Mr Fittler said his mate hadn't changed since he was diagnosed.
"When I speak to him it doesn't feel like he has dementia so at the moment Royce is Royce," Mr Fittler said.
Mr Simmons had a simple request for those that see him on his journey through the Central West.
"If you see a short, little fat fella walking can you please dodge him, don't run me over, that would be good," he said.