A miracle boy born with the ultra-rare "two face" condition has defied all odds to survive to teenage years.
Tres Johnson from Bernie, Missouri, celebrated his 13th birthday despite doctors giving him zero chance of survival at nearly every stage of his life.
He has craniofacial duplication, a disorder caused by the SHH protein that alters the formation of the skull and face. It is so rare, only 36 cases have been recorded worldwide.
Tres was born with a large cleft, his eyes spaced further apart, two separate nostrils, an abnormally shaped head and cognitive delays. He also suffers from seizures.
Parents Brandy and Joshua continue to fight for their son's life while amazed doctors do not understand how he is alive. Many with the condition are stillborn.
Tres 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.
The family battle horrific abuse from strangers who tell them to "kill it" and "put him down".
Brandy, 35, his full-time carer, said: "We don't know what will happen in Tres' future, no one thought he would be here today.
"It was very exciting celebrating his birthday, and emotional, but very surreal waiting for the big day. I was an anxious mess worrying about him.
"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.
"With other cases, there is a duplications of blood vessels in the brain leading to multiple brains, but Tres doesn't have that, making him different from all other cases.
"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.
"So many people that see what happened to our son, think of it as a tragedy but before I thought my son was going to die yet he's still with us today, to me that's all that matters.
"My goal is to keep him here and make sure he knows how loved he is, for however long he lives."
The family have received a range of hurtful comments about their son but instead of hiding, they combat the offensive ignorance with education and awareness raising.
Brandy said: "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.
"After so many years I've just had to swallow my pride, try to stay calm and explain my son's condition.
"After I talk to them they see things [from] my perspective and regularly ask how Tres is doing."
Tres received more than 14 diagnoses before it was recognised that he had craniofacial duplication, also known as Diprosopus, the Greek word for "two faces".
Brandy 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.
Despite this, he has intractable epilepsy meaning he suffers from more than 400 seizures a day. However, after exhausting all medical options, his mother now treats him with cannabis oil.
Brandy said: "Four years ago, we were told there was nothing more doctors could do for him.
"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 [18kg] and now is pushing 77lbs. 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."
The family say they have struggled to find help for Tres and claim that because of the rarity of his condition many doctors see him as a research project.
Brandy said: "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.
"We have only done the surgeries that were necessary, not any cosmetic ones, we are not ashamed of him or how he looks and never will be."
David A. Staffenberg, MD, pediatric reconstructive plastic surgeon at NYU Langone, said: "It's a rare disorder and in this child, we are probably talking either craniofacial duplication or something that may look similar. [In] these cases we see some anatomic element of the baby that is duplicated.
"In the centre of the baby picture, we can see the right nostril and at the top of the cleft lip is the baby's left nostril, between the two there is a small circular depression, this may be a small duplicated nostril.
"There's a protein that seems to play a great role in how the face comes together, it can determine the width of the face and plays a role in how the brain, organs, fingers and toes develop.
"Most of these disorders tend to be sporadic in their inheritance. It's likely that neither his mother or father had any history of it in their family; it's probably the result of a spontaneous mutation.
"It's almost like being stuck by a bolt of lightning, that's why it's not very common. If I was to stand outside to be hit by lighting I'd be waiting a long time: it's a genetic equivalent of that.
"The greatest challenge a lot of families find, in first or third world, is where to go. There are many medical centres around the world that offer the best care possible.
"As painful as it is to hear, more often than not parents are told the prognosis is dismal and nothing can be done.
"Mothers frequently describe being in [the] delivery room when their baby is handed to them and everyone in the room shrugs their shoulders. It's a heartbreaking scene."