"I thought, 'What does it mean for her future?'," Ms Behr said.

"But I also thought, 'What a relief', because I knew something wasn't quite right but I didn't know what it was.

"All I could think was, 'She's my little girl and I need to get her help, but I don't really understand it yet'."

Ms Behr said recent high-profile incidents, including the alleged confinement of a student with autism in an ACT school and a young boy with the disorder who went missing in Victoria for five days, showed many other people in the community also didn't understand.

It was a lack of public awareness of the disorder that inspired Ms Behr to walk and ride her scooter around Lake Burley Griffin for 24 hours from Friday afternoon.

She also wanted to raise money for Autism Asperger ACT, a non-profit organisation which has provided support and resources since Eden's diagnosis.

"I'm young, I'm fit and it's only 24 hours out of my life. When I first considered doing an awareness-raising activity, I thought about walking from Canberra to Darwin. But then I thought it would be better to do something that Eden could be a part of."

Canberra Raiders coach Ricky Stuart, an autism awareness advocate, will be at Commonwealth Place for the start of the walkathon, which coincides with Autism Awareness Month.

Ms Behr, of Casey, said her family had been on "a massive learning curve" since Eden's delayed speech, regular meltdowns and concerns from preschool teachers prompted her to visit a doctor.

"As a parent I kind of knew in my gut that something wasn't quite right with Eden but at first I just put it aside.

"As soon as we understood it and I knew why she was doing things it meant we could work around it and give her tools to deal with it."

Autism Asperger ACT project manager Susanne Morton said recent events showed there was a long way to go in breaking down stereotypes and stigma.

"There was this public outrage and there were a lot of things that were said that made me think people don't have a very good understanding of what it is.

"It seems to me that people who haven't had anything to do with autism spectrum disorders seem to think of it as disability.

"It's actually more of a neurological condition so it doesn't really impact intellect."

Mrs Behr believed some of the misunderstanding stemmed from the fact the spectrum was so broad and the disorder manifested differently in each child.

"They are such beautiful children, they just think differently to us. And who's to say we think the right way, anyway?

"They just have a different way of doing things."