The Poteez, which has been two years in the making, is now in production and is the brain-child of David and Maree Macey.

Maree suffers from the very rare degenerative disease Spondyloepemetaphaseal Dysplasia which affects only a handful of people.

It means the connective tissue and cartilage between her bones does not form properly.

As a result, Maree is not much taller than her six-year-old daughter Thalia.

She has had 22 operations and faces the prospect of more in the future, including knee replacements and even amputation of part of her legs.

"My parents were told that I would never walk and would have to be in a wheelchair," explains Maree.

"But my mum wasn't having any of that. She was determined that I would live as normal a life as possible."

However, despite her mum's and her own determination, Maree struggled physically at mainstream school and was sent to a special school, where she didn't fit in either.

"I was bullied at school because of my height and also because I couldn't do what the other children could. I had to wear callipers and after my operations was in a wheelchair.

"But people think because you have a physical disability your brain doesn't work either – that's just not the case."

Maree left school with no qualifications but was determined not to be beaten.

She embarked on a business and administration course before taking a job as a receptionist.

She has had to struggle against constant pain and often discrimination in the workplace, but she has never given in to her illness.

"There are people worse off than me; people with cancer who have not long to live. I may be in pain and have to undergo operations, but I am not going to die from it.

"I can enjoy my life, my husband and my daughter."

It was having their daughter Thalia that changed life completely for the Maceys.

When Thalia was nine months old, Maree had to undergo a hip replacement and was told she may end up in a wheelchair.

"I became quite depressed as it seemed so hopeless," says Maree.

"I saw a counsellor which helped. As Thalia got older, I struggled to lift her. I had to have a lightweight buggy and friends and family would help me."

But it was while trying to potty train Thalia the struggle turned into a bright idea.

"I really struggle to bend down and emptying the potty was always very difficult. David is very squeamish and in the end we decided to look for a disposable potty.

"But there was nothing available except a device with a disposable plastic bag which we thought sent out the wrong message to small children. David likes making items from cardboard and he made the first Poteez."

The idea had initially just been for their own use, but David soon realised that they may have hit on a winner.

They patented their invention and for the last two years have been trialling and altering their design.

"Poteez is truly disposable," says Maree, 32.

"It comes in attractive designs to appeal to little children and is made from recycled cardboard.

"You can use it, seal it and then simply put it in the bin. It is ideal for long car journeys, holidays or even when going out for a walk."

From having no qualifications, Maree is now a successful businesswoman and was last year shortlisted as Woman Inventor of the Year. The pair have appeared on Sky's The Big Idea presented by Ruth Badger, who was runner-up on BBC2 series The Apprentice.

"We are very excited about the future. Thalia has been brilliant.

"It is like she has always had a sixth sense. I struggle to bend down and she seems to know without being asked and picks things up for me. We just hope that Poteez will be a success."
Poteez costs £6.99 for five. www.poteez.com