Matthew - now aged six - was just six months old when he was struck down by a mystery infection which travelled to his brain, causing irreversible damage.
“The doctors didn’t know what had caused it,” says mum Leila, 30, today. “But they said the infection had taken the same form as the herpes virus.
“It could have been caused by something as simple as someone kissing him when they had a cold sore.”
It took only a few hours for Matthew’s family’s world to be turned upside down. Leila had noticed he was a ‘little off’ - suffering a raised temperature and lack of appetite - but it was when she went to put him to bed that she noticed a twitch in his face.
“I suppose it was a bit of a mother’s intuition,” she said, “but I knew then something wasn’t right.
“We went to the hospital that night - my dad driving us because my husband Steven was away.”
Over the following hours Matthew’s condition deteriorated and doctors at Sheffield Children’s Hospital ran test after test.
Leila said: “I had no idea what was going on at first - I knew he wasn’t right but I just expected it to be a virus or something that could be easily treated. A few hours later they started saying it could be meningitis.”
The situation only continued to get worse as time ticked on into the following day and night and Matthew began fitting repeatedly.
“It was horrific to watch,” Leila said. “That was the worst night of my life. Eventually they managed to get the fits to stop and sedated him and he was taken up to the intensive care unit.”
After a visit from the neurologist Leila and Steven, 33, were finally given the diagnosis that Matthew was suffering encephalitis.
Whereas meningitis affects the lining of the brain, encephalitis targets the brain itself.
Medics told the devastated couple it could have been caused by a kiss from someone with a cold sore.
Specialists could not initially tell the extent of the damage caused to Matthew’s brain, although initially he made good progress and was allowed home to High Green in Sheffield after two weeks.
“At first he was exactly the same child,” Leila said. “There were no after-effects.
“But we’d only been home about a week when things started to go downhill. One day I found him in his cot not responding to anything. He couldn’t look at me, he couldn’t turn his head, he was floppy.”
Matthew was rushed back to hospital and re-admitted - this time for three months. Leila said it was heartbreaking to find his condition going backwards again.
“We had been through all that nightmare initially and we thought we had come through the other side,” she said. “It was devastating to realise we hadn’t.”
An MRI scan was finally able to show up the damage caused to Matthew’s brain.
“They said the white bits showed where it had been damaged,” Leila said. “There was so much more white than anything else, we just could not see how he would be able to move on.”
Medics still could not tell the couple - also parents to Emily, 10, and Nataliya, four - what the long-term future held, advising them they would have to monitor his progress as he got older.
Leila said it was a “terrifying” experience taking him home for the first time and having to deal with all the related medications and contraptions that had been installed to allow them to care for and look after a disabled child.
And it was a steep learning curve as they dealt with the problems he faced since his condition had regressed to that of a newborn baby.
It was when he was around two years old that Leila and Steven - who works as a carer - first heard about the Cerebral Palsy Physiotherapy Centre, in Luton, which offers physio to help build strength and encourage development in children like Matthew.
Since then the couple have thrown themselves into fundraising to pay for the treatment which works out at more than £1,000 per two-week programme.
Over the years Matthew - now a pupil at Woolley Wood special school - has averaged two such courses a year, carried out in partnership with his regular NHS therapy, and the difference has been remarkable.
Leila said: “He has done absolutely amazingly! He has come on far more than we ever expected.”
The couple are keen for their son to continue the sessions and are fundraising for the next one - with a huge boost due to be provided by Leila’s best friend Steph Squires when she shaves off her hair which she has been growing for three years for the occasion.
She hopes to raise more than £1,000 - enough to pay for one whole course of treatment - with the stunt set to take place in May.
Leila said: “Steph has been incredible throughout it all - I can’t believe she has got the guts to do something like this! But I think it’s amazing and we’re so grateful as a family that she’s helping to give Matthew the best possible chance.”
n Email Leila at email@example.com to sponsor Steph.