Joyful cries ring out as three-year-old twins Rebecca and Jack pedal their tricycles across the lawns of an Abbots Langley housing development, looking for all the world like any other children their age.

But the twins were both diagnosed with a form of cerebral palsy just after their second birthday and the bikes they are riding were specially designed to suit their needs.

The trikes were bought secondhand and broken before being modified by engineers at an Abbots Langley charity – a process paid for by a £550 donation from the Watford Lions.

Design and Manufacture for Disability (DEMAND) completely refurbished the tricycles and modified them to allow Rebecca and Jack to play as any other child would. The cycles are also designed to help them to build up muscles in their legs while they play.

During a presentation on Monday (September 3) at the charity’s base in the former chapel on the site of the old Leavesden Hospital, dad and full-time carer Kevin Latham, 52, said he was overjoyed at the donation.

He said: "These are going to make such a massive difference. We have had them for a few months now and we go riding in the streets and around Bury Lake in Rickmansworth.

"It is now just a normal activity for them. They enjoy it and it has made a tremendous difference to them."

The twins’ mother Caroline, 32, a finance manager, said: "They are bright, happy, children who get stuck in at their local playgroup, have learned their colours and numbers and love to read. We are so proud of them.

"Put them with any bunch of kids their age and you wouldn’t easily pick them out - except when the running around starts. Jack and Rebecca have to crawl or grab their walking frames to join in. It’s heartbreaking to watch them trying to keep up."

The family, who live in Hangar Ruding, Carpenders Park, are currently fundraising to pay for Rebecca and Jack to travel to America for selective dorsal rhizotomy (SDR) treatment - a procedure that will cost £25,000-£30,000 for each child.

Denise Gillies of DEMAND said the charity carried out a number of commissions for converting second-hand equipment to accommodate disabilities but relies on word-of-mouth to get its message across.

She said: "One size does not fit all and often there is an engineering solution available but where there isn’t, we make things from scratch.

"I hope the success of the Paralympics is going to lead to an increase in awareness and enable us to reach more people.

"We already give talks in schools about our services and one of our sources of revenue is making boccia ramps exactly like those used in the Paralympics."

David Warren, chairman of services at Watford Lions, said: "The Lions funded the purchase of the machines. This is something that has been talked about for quite a while. Hopefully the children will have very good times on the trikes."

To donate to the twins’ cause, please visit: http://www.dreamtowalk.co.uk/