With her blonde hair, youthful complexion and brown eyes, Ashleigh Harley looks every inch the model, social media influencer and budding writer and film-maker.

But, for Ashleigh, that's a problem she is addressing in a new documentary.

Ashleigh is one of millions of people who live with a hidden disability.

In her case, it's a rare condition called Ehlers-Danlos Syndrome (EDS), which can leave people in crippling pain, suffering from weakness in muscles and tendons. It can cause joints to pop out of their sockets.

"There are 13 different subtypes of EDS," explains Ashleigh. "And there are 255 million people in the world with all the different subtypes. The result is a very misunderstood condition."

Ashleigh was just 12 when she was diagnosed with EDS and that came only after months of travelling back and forth between London - where her family consulted specialist doctors - and her home in the Midlands.

"It was pretty terrifying to be honest," she explains, "because at first we didn't know what it was when the condition first came on. I would just go blind and be paralysed for a few days. We were just all really scared.

Image copyright Ashleigh Harley Image caption Ashleigh is a keen showjumper and is campaigning to include the sport at the Paralympics

"It was a relief to know what it was at the same time. It's currently a case of managing it."

There is no cure for the condition so "managing it" means a lot of daily medication and putting up with the painful effects of EDS.

"I can't eat solid food. And today, I haven't even been able to drink water because I keep throwing up. It's difficult actually for the doctors to be able to prescribe medication I can tolerate because I have allergies to the intravenous medications."

A deformation in Ashleigh's spine has also been caused by the illness, which requires her on occasion to walk any distance using crutches.

What is Ehlers-Danlos syndrome?

Ehlers-Danlos syndrome affects connective tissue which supports skin, joints and bones

Symptoms include joint hypermobility, dislocations and stretchy skin

People with the condition can bruise and fracture easily - and are often in chronic pain

Source: NHS - Ehlers-Danlos syndromes

But despite the problems EDS has caused her physically, often suffered behind closed doors, it has lead to Ashleigh feeling discriminated against, albeit unwittingly, by people when they comment "on how well I look".

"I say, 'well you didn't see me throwing up this morning'. People don't understand that you can look well, and be living with a chronic condition."

Ashleigh, who wrote and directed a short sci-fi film called The Wall of Lyon, which showed at film festivals around the world is now working on a new film, The Dark Horse, which aims to shed light on her disability.

She says it has taken her a long time to be able to find the confidence to speak out about her condition.

"I was bullied quite badly for being ill," she says of her childhood. "As a result of that, I felt quite terrified of telling anyone. But then I just realised that there's no point in being anything other than what you are.

Media playback is unsupported on your device Media caption Ellen has Ehlers-Danlos Syndrome, a condition that affects connective tissue and joints

"So it was time to just stand up and say that this is the truth."

Part of the new film focuses on Ashleigh's attempts to have showjumping recognised as a Paralympic sport.

Equestrian events became a part of the Paralympic Games for the first time in 1996 in Atlanta and is open to athletes with any type of physical or visual impairment.

But disciplines are limited to dressage events, a championship test of set movements and a freestyle test to music.

Team GB have enjoyed a huge amount of success in the field, winning more than 30 gold medals.

Image copyright Ashleigh Harley

Ashleigh - a keen jumper from her early years - says the sport has helped her cope with the impact of her illness.

"I wanted to overcome my physical limitations, as I think a lot of people in my position do," she says. "Because I've loved horses most of my life, I just couldn't stop myself riding any more. So I turned to my parents one day and said, 'I really want to get on a horse again'.

"I realised that despite my limitations, I can still rise and find a way to get around a course of show jumps."

Announcing her intentions on FaceBook, she says she has since had messages from all over the world.

"[They] are desperate to compete in Para-showjumping, but just don't have the opportunity because their country isn't supporting the sport."

According to Ashleigh, in order to get the International Paralympic Committee to recognise the sport, it would require more than 30 countries organising regular competitions.

It's a Herculean task, but Ashleigh is convinced it can be done.

"At the moment, we've got Britain and we've got Germany, we've got France and Ireland. And there's been a lot of interest from America and Russia as well.

"I'm literally at the point now where I'm going to the IPC at the end of the month and we're starting to talk about it."

Her efforts have been applauded by British Showjumping, chief executive Iain Graham said: "Ashleigh is incredibly inspiring, not only in the way that refuses to let her disability stop her participating in the sport she loves but also in respect of her wanting to raise awareness of the the para jumping competition structure that we have put in place so that other like-minded people can participate in it.

"With Ashleigh's passion, vision and personal drive to make other nations sit up we may well be on the way to delivering this sooner than we had hoped."

While the destination is clearly important to Ashleigh, the ultimate recognition of Paralympic showjumping, the journey is of equal importance.

"The thing I would like to see is people starting to look around and not make assumptions on other people that their life must somehow be better.

"It'd be hard to measure but if I could make that change in any small way, I'll be happy."

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