Mitchell's dad Luke Glynn said his son asked how the boy would get hair. After some online research, they found people could grow their hair out and then donate it for a wig.

"Then it came January and it was time to go back to school and we said 'rightio mate, time to get a hair cut' and he asked if he could just get the sides done," Mr Glynn said.

"We thought that was a bit strange and asked why and he goes 'I want to grow it to give that boy some hair'."

Mitchell, who is now 12, will finally be cutting his hair in October, after years of growing it to meet the requirements. His hair needs to be at least 35.5 centimetres and it can't have had any dye in it for at least 12 months.

When it's cut off, it'll be put into a ziplock bag and sent to Variety the Children's Charity as part of their Hair with Heart campaign.

It will then be turned into a wig for someone without hair due to a long-term medical condition.

During all the time he's been growing it, Mitchell said he never really thought of giving up his goal.

"I thought it was a really good cause so I just kept on going," he said.

His hair has sparked a lot of comment and questions but Mitchell is used to explaining why it's long.

"I say I'm growing my hair to cut it off to donate it to people with cancer that can't have hair, unfortunately," he said.

When he is finally free from the long locks, the 12-year-old said he "honestly [didn't] know" what it would feel like.

"I'll probably be shocked and confused about who I am," he said.

Mr Glynn said wigs could cost up to $6000, and generally they only lasted about two years, making it very expensive for families.

While he was shocked at Mitchell's idea at first, Mr Glynn is full of support of his son.

"Both myself and my wife are extremely proud of him. He's an extraordinary young man," he said.

"He could have given up a long time ago and he hasn't and that's what makes us the proudest. If we'd have said it's not long enough he would have kept going. We've made sure he's had plenty of length there to keep going."

Mitchell is also hoping to raise $1000 for the charity.

So far about $250 has been donated.

Mr Gynn said the money Just Cuts at Dubbo Square waived on Mitchell's hair cuts for the last three years would also be added to the total.

Donate at: hairwithheart.variety.org.au/fundraisers/mitchellglynn.

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