Mum Callie Blackwell gave her dying son Deryn cannabis to ease his cancer - and he made a full recovery
As a parent, your job is to protect your child from harm.
However, it's not always possible - and that's the devastating reality that Callie Blackwood had to endure.
When her son Deryn was diagnosed with leukaemia at the age of 10, he began chemotherapy straight away and was amazingly back to school within a couple of months.
Callie and her son Deryn appeared on This Morning today (Credit: Facebook/ Callie Blackwell)
But in January 2012, Deryn's throat began to hurt and he had his tonsils removed, which were found to be cancerous.
It took the doctors a few days to diagnose what type of cancer this was - because they'd never seen it before.
The cancer was found to be Langerhans cell sarcoma - which is so rare that only five people on the planet have ever suffered from it.
The one in seven billion cancer is aggressive, and so little is known about it that even Deryn himself isn't sure how to describe it.
Speaking to Phillip Schofield and Holly Willoughby on This Morning earlier today along with mum Callie, Deryn said: "There's not a lot of research into it so I'm not too sure what it is, it's very confusing."
He described how he was given a bone marrow transplant to try and help, telling the presenters that he'd had "extensive" chemotherapy and radiotherapy and then a bone marrow transplant.
Deryn was diagnosed aged 10 seven years ago (Credit: Twitter/ Deryn Blackwell)
The now 17-year-old had three attempts at a bone marrow transplant, but unfortunately they all failed. Mum Callie described how at the fourth transplant, it was their last shot.
She said: "They only had one more bag of his own cells - no more. They stressed to us that there were no more chances after this."
Callie then explained that three days after the transplant, Deryn had trapped his hand down the side of the bed and contracted some infections - deadly for someone with no immune system, saying: "He was being kept alive by antibiotics.
"He had been really upbeat and jovial throughout everything, but those last few months he was in a lot of pain."
The pair appeared on This Morning to discuss how Deryn had recovered (Credit: ITV)
Callie, from Bury St Edmunds, said that the family were given "three days, a week at most" as a prognosis for Deryn, with the boy admitting that he had planned his own funeral.
He admitted: "I wanted to go. I did," with Callie adding: "He was looking forward to it." Deryn went on: "After four years of treatment, enough was enough."
At the family's lowest ebb, Callie made a controversial decision that would turn out to be an excellent call - but could have landed her in jail.
She said: "I'd done a lot of research. Over the next couple of months, cannabis just kept popping up on the internet. I would dismiss it as an option, but it got to the point where I was in hospital with Deryn, and he was so incredibly ill that I just tried it and asked the nurse for a cannabis-based pain relief called Bedrocan, who refused because it has not been licensed for children."
At this point, Callie said: "What have I got to lose? He's dying anyway."
She described how the effects were almost immediate and "blew her mind". She was hoping that it would alleviate some anxiety and pain for her son, but was not expecting what happened next.
Deryn was ready to die after four years of treatment (Credit: Twitter/ Deryn Blackwell)
Callie described how, within an hour of administering the tincture - which she stresses is NOT cannabis oil - Deryn had "chilled out": "He just relaxed - the anxiety had stopped, he was no longer panicking."
The family found that Deryn's white blood cells started to increase after five days. They also noticed that has poorly hand, which they were told would have no chance of recovering, had started to heal.
She explained that nobody has ever seen positive results from a bone marrow transplant after 50 days, so for Deryn to start getting these positive results at day 75 was nothing short of a miracle.
Callie has now written a book on the family's experience (Credit: ITV)
The family even tested it by withdrawing the cannabis solution - and they saw Deryn's white blood count drop by half, so they knew it was definitely having some sort of positive effect.
And now, five years later, Deryn is "perfectly healthy". The family stress that they are not advocating it for everyone, but that it did work for them.
Phil and Holly then explained the laws around cannabis in the UK, with Callie admitting that she could actually be prosecuted - but it's a risk she was willing to take.
What a miracle!
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