A healthy boy became unable to move or breathe unaided after contracting a rare immune disorder. When four-year-old Harrison became unwell with scarlet fever, he initially seemed to get better. But a few weeks after getting the infection, he woke in the night with a rash developing on his legs. He was taken to his local hospital where doctors were left bewildered as to what was making him so unwell.

Meanwhile, his condition was quickly getting worse and he started complaining of a burning sensation in his legs. His mum Alex said: "Whatever it was seemed to be rising from his legs up. What started as unsteadiness on his feet progressed to no sensation in his legs leaving him unable to walk. His voice also became very squeaky and while he had a little cough, it was as if he was unable to clear his throat with a full cough."

He was rushed to the critical care unit at Noah's Ark Children's Hospital. Overnight, he went from a happy, active little boy to a child who couldn't move, eat or breathe for himself. He sedated and ventilated for three weeks while doctors tried to control his symptoms - and his shock change in condition was later diagnosed as Guillain–Barré syndrome, a rare disorder affecting the peripheral nerves.

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The syndrome is often preceded by a viral infection like Harrison's, which makes the immune system attack itself. It usually starts in the lower limbs, resulting in weak muscles or paralysis. After a nerve-wracking wait for the whole family, Harrison was weaned off the ventilator to the point where he is now able to breathe unaided.

He was moved to the hospital's Island Ward where occupational therapists and physiotherapists have helped him with his rehabilitation. His goal is now to get into the pool by himself when he visits Center Parcs later this year. For the latest Welsh news delivered to your inbox sign up to our newsletter.

Earlier in April, Harrison celebrated his fifth birthday with something very special. Two months into his stay at Noah's Ark, an orange Lamborghini came to visit - organised by "sparkle co-ordinator" Emily, who is funded by the Noah's Ark charity to work with the play team on Island ward to brighten up Harrison's days.

Harrison smiling towards the camera on a beach with bright blue sea in the background. He is wearing an orange t-shirt
Harrison was previously healthy but a single case of scarlet fever changed everything
Harrison sitting in a wheelchair looking towards the camera. He is wearing a blue undershirt, white tshirt with a sports car on it, and a green blanket
His parents wanted to thank Emily from Noah's Ark

Emily started taking therapy dogs in to visit Harrison while he was still in critical care, and brought him treats and glitter tattoos when his condition improved. Alex said: "Emily is absolutely amazing. She has made the effort to get to know Harrison and his likes and dislikes, so when it came to his birthday she knew exactly what to do.

"Harrison was absolutely amazed to be taken outside to sit in a real Lamborghini and be given a mini version of the car as a gift – though we all laughed when he was almost as excited to spot a passing bus! You could see that Emily was so genuinely happy for him on his birthday which as a mum was such a lovely thing to see."

A Noah's Ark charity spokesperson added: "Harrison’s recovery to date has been a testament to the resilient little boy he is. Harrison’s story is an example of the many touchpoints our supporters have in the care of young patients at the Noah’s Ark Children’s Hospital for Wales.

Harrison in bed smiling
Harrison has been making big steps in his recovery
Harrison sits in the passenger seat of orange car
Harrison enjoyed sitting in an orange Lamborghini as a birthday treat

"Your donations helped to build the hospital that houses all the specialist teams involved in Harrison’s recovery. You helped fund the machines that helped Harrison breathe when he wasn’t able to and the play team who support and distract Harrison through play. You also make it possible to fund sparkle co-ordinator Emily, whose sole job is to bring smiles and happiness to the lives of young children in hospital."

The Noah's Ark charity, which raises money for the children's hospital, is holding its Superhero 5K family fun day on Sunday, June 30, where people can walk, wheel or jog to raise funds to support young patients. You can see more details here.