News, views and top stories in your inbox. Don't miss our must-read newsletter Sign up Thank you for subscribing We have more newsletters Show me See our privacy notice Invalid Email

When Liam Derbyshire was born, doctors said he would not live for more than six weeks. In a few months he will turn 18.

It is estimated that in the world only 1,500 people have the same rare disease as the teenager .

Liam was born with Ondine's Curse, officially known as Congenital Central Hypoventilation Syndrome, which causes respiratory arrest due to a patient's lungs not functioning when they are asleep .

The condition means the 17-year-old has to be plugged into a life support machine and watched by a carer every night to keep him alive.

Doctors gave Liam just six weeks to live after birth, but later this year the young man from Gosport, South Hampshire, is turning 18 and has truly defied all odds.

Liam's parents, Peter and Kim, act as a major part of his caring team and monitor their son 24 hours a day with specialised GPS equipment.

(Image: Barcroft Media)

Kim, 56, said: "Central Hypoventilation Syndrome basically implies that when you sleep, your phrenic nerve doesn't kick in so your brain doesn't tell you to breathe.

"We rely on a machine to make him breathe and without that, he wouldn't be alive. If he doesn't breathe, he dies - that's it.

"His condition is extremely rare and if we would have listened to some doctors he shouldn't be alive right now.

"He had the intent for life and so that became our job to make sure he was offered that."

Liam's condition means he has a very strict bedtime routine.

Dad Peter usually takes charge of plugging his son into the ventilator machine and making sure everything is in order for the carer to sit and watch him sleep.

He said: "If you ask me if I had a good night sleep the answer is no, not since the day he was born to be quite frank.

"You are constantly on the alert and you worry that perhaps it's the last time you are saying good night.

(Image: Barcroft Media)

"Liam's sleeping arrangements are the electric bed which has three positions - it can be up or down and the head and feet can be lifted independently in order to give him some quality sleep.

"On the left hand side we have all of his ventilator equipment. The idea is that a ventilator supplies positive pressure so that Liam is actually forced to exhale CO2, which normally you or I would [naturally].

"There is also a plate under the mattress that will sense any sort of fitting and then the only way of making sure that he is still breathing is via that type of mask.

"Besides a medical room, it's also his room and so you have got his PlayStation, the set TV and then Liam's big forte - his Lego, which is all around the room."

Liam also struggles with a bowel condition, something unrelated to Central Hyperventilation, which means he must eat substantially large portions of food throughout the day to keep his body functioning.

Kim said: "He lost a substantial part of his bowel when he was first born and now has an ileostomy bag, which he has had for many, many years.

(Image: Barcroft Media)

"Food is a big issue for Liam. I have to plan every day and every way - the amount of food he goes through is quite terrifying.

"I have a budget given to me by my husband for food of around £800 a month but I would be lying if I didn't say we actually spend more than that.

"It can be quite terrifying when people say how much I actually have to spend to keep my son alive. But I don't have any choice.

"It's imperative that he has drugs with whatever he is eating or he can begin to lose weight extremely quickly."

There are two prominent medications that Liam still takes - Tegretol, to monitor his seizures, and liquid Imodium for his stomach.

Liam finds it hard to understand how he suffers compared to those people around him and his mental state is not the same as a typical 17-year-old.

Peter said: "His mental state is unknown to be perfectly frank.

"Crossing the road and all of the other normal life skills are way behind the curve, if you will."

(Image: Barcroft Media)

Kim added: "It's about trying to make him become more aware of what he is dealing with. We are not going to be here forever.

"You are trying to plan how he is going to cope on his own."

Liam has a large family with an older brother, two sisters, three half sisters and eight nieces and nephews, and he spends a lot of time socialising with them.

He also manages to attend a normal school where he gets on well with both staff and students.

Kim said: "He gets on extremely well with the staff and one lad in particular, Jordan, whom he knew when he first joined the school.

"His favourite hobby would have to be drawing - he has at least a thousand pens and also his Lego creations - he is fascinated with that.

"He is quite arty and I think he gets that from me. But his attention span isn't always great and you have to make the most of the few minutes you get."

(Image: Barcroft Media)

With regards to Liam's life expectancy, Peter suggests more research is being done for a treatment to Central Hyperventilation but maintains that no one really knows what age Liam could live to.

He said: "We have gone from nothing towards 18. The future for Liam I would say is, it's not going to be totally independent.

"I mean to a certain extent he has been protected by his own condition that he doesn't understand certain things.

"I'm extremely proud of him. I personally would have given up a long time ago. I couldn't have lived with the condition he has and put up with what he has with the pain levels."

Kim continued: "Liam is 17, nearly 18, so it's a big birthday this year!

"He is an annoying, grumpy teenager so he is no different to any other teenager but he does have a sense of humour and he is very caring - he's got a really soft side.

"You can't regret anything you have done - we've had 18 years of his life so day to day you can't regret anything."