Noah Wall is a boy from England who was diagnosed with a birth defect called spina bifida in which the spinal cord and the brain form without becoming fully enclosed.

He was born with only two percent of his brain, leaving his parents discouraged for any chances of survival from this devastating condition.

On paper, a myriad of other health complications like Edwards Syndrome and Trisomy 13 would indicate he has everything working against him.

But Noah is meant to be here.

He defied expectations after being born and the six-year-old continues growing and his brain shows signs of development.

His survival that could only be described as "extraordinary" according to his parents is confounding medical experts.

In a miraculous turn of events, the six-year-old's parents, Shelly and Rob, told Good Morning Britain that their son has gained function in 80 percent of his brain.

The boy learned how to talk and is hoping to be able to walk, in addition to surfing and skiing with the help of a pioneering clinic in Australia where medics assist him with physiotherapy and cognitive training.

Rob described Noah's prognosis as being grim from the outset.

"It's a very emotive subject," he said.

"Some people say you can't grow a brain."

"Other people say it must have always been there. But if it was and squashed up it would have been so severely damaged he would have been very mentally and physically disabled."

Shelly said:

"Before he was born they gave me the option of a termination five times."

"We got taken into a room and they drew a circle saying 'this brain will only be half a brain."

The devastated parents also signed a "do not resuscitate order" and began making funeral arrangements before their baby was born.

Shelly delivered the baby via C-section on March 6, 2012 because Noah's head had grown so large due to hydrocephalus – a rare brain condition in which excess buildup of cerebrospinal fluid within the ventricles, the empty cavities inside the brain – can permanently damage mental and physical abilities and lead to death.

One parent related to Shelly and Rob's experience and shared his own story about the daughter he almost lost to Non-ketotic hyperglycinemia (NKH), a metabolic disorder.

Noah has become a beacon of hope with his incredible story of survival.

His charming personality and infectious smile are a bonus and are his contributions to a world prone to skepticism.

The parents are helping to raise awareness on their Hugs for Noah website, which chronicles Noah's ailments and his journey of overcoming insurmountable odds.

Shelly is informing women to take plenty of folic acid, a B vitamin, before and during pregnancy to help protect the spine and brain from birth defects.

"Even though I took it I didn't take it early enough," she said.

"No one told me just how important folic acid was."

Noah, who is currently confined to a wheelchair, will continue a lifetime of surgeries but Shelly and Rob are aiming for their son to eventually be able to walk.

With his track record of overcoming obstacles, we're optimistic he will continue to rise above.