Wife Liz Duncan said because of the debilitating nature of motor neurone disease, people needed a village around them.

And for the Duncans that was their church, school and surf club - and the three have pooled their efforts to organise the July 16 fundraiser.

Rob showed enormous courage in his fight, Mrs Duncan said.

"He had a very strong faith which helped him face up to what was such a tragic diagnosis but a really sure hope for the future as well," she said.

For the family, the diagnosis came "out of the blue".

The first sign of the illness was when Rob started to lose his balance, he then developed a limp and then started having trouble doing up buttons with his hands, putting his socks on and doing up zips.

"With MND it takes a while to diagnose because there is no definitive test - you've actually got to rule everything else out," Mrs Duncan said.

Within about six months of diagnosis he was in a wheelchair and then within another four to six months he had lost the ability to speak clearly and swallow.

"By the time he passed away he was literally bedridden but his brain was exactly the same," she said.

"He used assistive technology to talk to us through a computer in a really slow pace but his mind was exactly the same as it always had been, incredibly sharp and intelligent but having to endure everything else shutting down.

"Even if your big toe was itchy you could not scratch it and you could not tell someone to help you very easily.

"They talk about the thousand goodbyes because you are saying goodbye to your body functions, the person as you knew them little-by-little, day-after-day.

"He didn't quite make two-and-a-half years post-diagnosis. He was 46." But before he got sick, Rob loved the great outdoors and being active. "He loved four-wheel-driving and being with his family and watching his kids grow up," Mrs Duncan said.

"Because the kids were so young, Rob and I were really intentional about making sure they tried to have as normal a life as you can when someone in your family has a terminal illness."

That meant staying active and being involved in the surf club.

"In some ways the fun run is a great way to honour that and to honour the fact that we ran, and there are lots of people in our community with disabilities that can't or illnesses that stop them from enjoying running in this beautiful place," she said.

Harriet, 12, said her favourite memory of Rob was the daddy-daughter date he had taken her on to Pippies soon after he was first in a wheelchair.

"I miss him heaps," she said.

Sam, 10, said his favourite memory of his dad was before he got sick helping him learn to skate on his long board. "I wasn't that good and I fell over but he kept telling me to 'get up and keep going'," he said.

The siblings said their dad was "very encouraging", "very brave" and "he didn't stop fighting".

King's College teacher Carin Wills said the event was their way of showing support and to help others who might be going through the same thing.

The fun run from the surf club to the Hopkins River - over 2km, 5km or 10km - starts at 8.30am on Saturday, July 16 and will be followed by a free sausage sizzle.

Mrs Duncan said that MND Victoria - whose motto is "until there's a cure there's care" - provides advocates for families, equipment and education.

"Because it's pretty rare, particularly down here in the south-west we were able to continue living down here and get all the gear we needed from our doctors and South West Healthcare and the MND clinic and MND Victoria," she said.

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