A family who put everything into caring for their severely autistic twins fear years of progress will be lost if a huge solar farm is given the go-ahead.

Jacob and Samuel Montague, 13, have therapy each day at their home in Cleve Hill, Graveney, just metres away from where the UK's largest solar park could be built.

For years, their behaviour was almost impossible to cope with as, unable to make eye contact or interact with others, they lashed out and at times became violent.

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But thanks to the incredible efforts of their parents Mark and Annie, the twins have flourished under the Son-Rise Program - an alternative course of child-led therapy.

The couple - who took Jacob and Samuel out of school due to grave concerns about their welfare - have built two rooms in their home, where their sons are now home-educated and have therapy with their parents and carers.

It has been so successful that Jacob has now been re-diagnosed as moderately autistic, and little by little, both boys are beginning to speak.

But a peaceful environment is essential and Mark and Annie fear that if the 1,000-acre development is approved, everything will change.

A critical worry is noise - both during construction, when at times more than 100 lorries are expected to pass through their tiny village each day, and upon completion, when it is feared the solar panels will create a constant background hum.

While to most people this would be an annoyance, to autistic children, noise can be distressing and even painful.

"A lot of autistic people have problems with things we don't even notice, like fluorescent lights," says Mark.

"Both of them were in a terrible state when they came out of school. They didn't talk, they didn't look at you, they didn't interact, they were totally alien to family life.

"Now, we tick stuff off the list that experts said would never happen. A lot of people don't even realise they're autistic.

"We got this far, we have struggled through so much, and the boys have done so well. Then this comes along. It would finish us."

The twins' story, which has been the subject of a BBC documentary, has inspired other parents to try Son-Rise and many have visited the Montagues to learn from them.

Mark and Annie had even wanted to start a special needs school for other children but now have no idea if they can stay in their home.

"We would be in a house that we can't live in," Mark continued.

"We just don't know what we will do. There's no way that we could move, because it would take more than we have got.

"Everything we have got goes into their therapy, so it's not as if we have got a valuable property that we could sell and just move.

"If this goes ahead, then it's two of the most vulnerable children in Graveney that will pay the price for it.

"The setting is absolutely fundamental to their therapy. They know the area well and they have contact with nature - they're the best foragers you'll find.

"The quietness here, that's what we love. This will absolutely devastate us."

Mark has raised his concerns with Cleve Hill Solar Park Ltd, which is behind the development, but has been told nothing about how his children's needs will be taken into account.

"If this goes ahead, then it's two of the most vulnerable children in Graveney that will pay the price for it" - Mark Montague

"We have asked the developers a number of questions and they just don't get back to us," he said.

Cleve Hill Solar Park Ltd says predicted noise levels at the closest homes to the site have been assessed.

Spokesman Emily Marshall added: "A construction traffic noise assessment has also been undertaken.

"There will be no significant noise impacts and we are looking at ways to further mitigate any short-term noise impacts, eg. during construction, through construction traffic management measures.

"Once the project is operational the panels themselves do not make any noise."

She added that the project team has twice met with Mark Montague to discuss his concerns.

"Mr Montague’s property is over 300 metres away from the closest infrastructure in the current development layout," she said.

"We are aware of his concerns and those of other residents of Cleve Hill about the proposals. In response, we have removed panels and associated infrastructure from the areas closest to Seasalter Road at the south eastern extent of the development site.

"We are continuing to consult on our traffic management proposals to ensure that concerns raised can be addressed as far as possible in the application. We expect to undertake further meetings with local representatives to discuss traffic management in the near future.

"The area of land between the Montagues and the solar development is currently proposed to be managed for biodiversity, potentially as a wildflower meadow or possibly some form of community orchard or woodland. We would be interested to hear from Mark and his family, and anybody else with further thoughts on how this land could be best utilised for the benefit of the local community and biodiversity."

Mr Montague says both of his meetings with Cleve Hill representatives were with other residents, and he has not received answers to follow-up questions he posed to the firm.