Tres Johnson has craniofacial duplication and doctors told his parents Brandy and Joshua that their son was unlikely to survive at almost every stage of his life, The Sun reports.
The youngster, from Missouri, USA, was born with a large cleft, two separate nostrils, an abnormally shaped head, cognitive delays and suffers seizures.
There are only 36 people in the world with the condition — caused by what’s known as the Sonic the Hedgehog (SHH) gene which alters the formation of the skull.
Tres has amazed doctors, who didn’t expect him to live and four years ago said there was nothing more they could do after reaching his teens.
He has undergone multiple operations to reshape his skull and close his cleft, as well as treat his seizures, which have reduced from 400 to 40-a-day since starting cannabis oil treatment, his parents explained.
Tres received more than 14 different diagnoses before doctors realised he had craniofacial duplication, also known as Diprosopus — the Greek word for “two faces”.
Brandy, 35, who is also his fulltime carer, said: “He was adorable and shocking at the same time, one side of his face looked like our older son, the other resembled our middle son.
“When he was born he had such a large cleft that it went up into his nasal passage and you could see into his sinus cavity as it was all open.
“His one eye looked like it was bulging out and the other sucked in, because his eyes are further apart he sees peripherally instead.”
Doctors doubted whether he would survive and mum-of-three Brandy says the first glimpses of her son were difficult.
“When they bought him into my room he was hooked up to a carrier box with all of his monitors, the only thing I could touch was his leg,” she said.
“Doctors weren’t going to sustain Tres and planned to let him pass if my husband hadn’t fought for him.
“Once I found out he was here and still alive that was all that mattered to us, we were always in it for the long haul.”
Since then, Tres has undergone numerous operations to close the cleft and efforts to reshape his skull to help relieve pressure on his brain.
Despite this, he has intractable epilepsy meaning he suffered from more than 400 seizures a day and after exhausting all medical options his mother now treats him with cannabis oil.
“Four years ago, we were told there was nothing more doctors could do for him,” Brandy said.
“I did a lot of research and the first week using Cannabidiol his seizures went down to under 40 a day, in over two years he has had over a 90 per cent reduction in seizures.
“He is cognitively improving and his size more than doubled, he was under 40lbs and now is pushing 34kg, he is constantly growing stronger and smarter.
“Using cannabis oil is the best decision I ever made though it has also been one of the hardest.
“Tres reaching the age of 13 is a huge deal, it’s surreal knowing he’s made it this far, the past 13 years have been nothing but a fight for survival.
“I lost count of the amount of times we were told he wouldn’t make it but here he is today a teenager, we now ignore their predictions and just focused on one day at a time.
“There’s not a lot known about the condition, most cases have duplication of facial features, some with four eyes, two noses and mouths, but many are stillborn.
“He is developmentally delayed, because he has cysts in his brain, mentally he is at the age of an infant but he is progressively improving in all areas.
“Mobility wise we were told he would never walk, but that doesn’t stop him from trying and scooting around on his butt.
The family have received a range of hurtful comments about their son but instead of hiding away they combat the offensive ignorance with education and awareness raising.
“I’ve heard every comment you can imagine over the years, from ‘kill it’, ‘put him down’ to being called ‘selfish’ for keeping him alive,” Brandy said.
“After so many years I’ve just had to swallow my pride, try to stay calm and explain my son’s condition to them.
The family say they have struggled to find help for Tres and claim that due to the rarity of his condition many doctors see him as a research project.
“It’s been hard for us to find a doctor who will treat my son as a person and not a case study, many have offered to work with us but not with my son’s best interest at heart.
“One offered us a ‘miracle surgery’ to make him look normal, but I don’t care about how he looks, what’s important is he is alive and comfortable.
This article originally appeared on The Sun.