Around two months after his third birthday, Isaac started experiencing repated bouts of high temperatures. He would be sent home from nursery and be back to his normal self after a little bit of Calpol.

But as it just wasn't going away, mum and dad Sinead and Gareth from Aberdare started to take him to the GP. It was an infection they were told, but doctors weren't quite sure of the source.

One day, Isaac's temperature spiked over 39°C, so their doctor sent him to be admitted at Prince Charles Hospital in Merthyr Tydfil. Again, they were told it was an infection and more antibiotics were prescribed. For the latest Welsh news delivered to your inbox sign up to our newsletter

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But the problem still didn't go away, Isaac was still experiencing temperatures. He was also showing signs of problems with his balance and was back and forth to the doctors as a result, until his own words changed everything. Upon another admission at the hospital, when he was about to be discharged, Isaac said: "My head is hurting."

"He was like a child possessed," said mum Sinead. "He started screaming saying he had a bad head. He had never said that before. We look back at pictures now and from about November we can start to see the difference. He had bags under his eyes he lost about 10lbs. It doesn't look like our child."

Isaac running on the beach
The mass was affecting Isaac's balance

The consultant decided to send him for a CT scan, which revealed a large mass on his brain. "It was on the left hand side of his brain and it was three by four centimetres big."

The family were then blue-lighted to Noah's Ark children's hospital in Cardiff where doctors ordered further scans to see if the mass had grown. Mum Sinead, 34, explained: "They were pretty sure it was a tumour. They said that they would only operate if it was a tumour and they planned for the operation to happen on the Thursday."

They were told that the other option could be an abscess, which would not be operated on and only drained and treated with antibiotics, but doctors were convinced it was a tumour, so an operation was scheduled. The word "mass" was first mentioned to the family on Saturday, by the morning of Thursday, December 7, Isaac was being taken down for a major operation on his brain. Sinead was six months pregnant at the time with Isaac's litle brother Dylan. It was an incredibly stressful time for the family.

"That was the worst morning, I just remember waiting. I remember looking at the time and checking it again and thinking surely an hour has passed, but it was just two minutes," Sinead said.

Isaac with a scar on the back of his head
Isaac's scar is now healing great

The operation lasted several hours, then Sinead and Gareth were told that the mass was not a tumour, but was an abscess after all. Still to this day, doctors don't know what caused it, but they were told it could have been a bacteria from a bug that travelled to his brain or something he was born with. Doctors said that while it was not uncommon, it was rare to occur in somebody so young.

"He had major brain surgery, he had the best treatment he could have had," said Sinead, adding that Isaac's recovery from the major operation was fantastic and within three days he was walking again. The surgeon told the parents that the position of the abscess was in the "best possible place" in terms of enabling a full recovery.

Isaac was in Noah's Ark until December 22 before being moved to Prince Charles Hospital where he was allowed home, only returning daily for antibiotic treatment, "which I think helped in the sense, him being at home, helped him to recover quicker. He had his own bed, his own toys, he wasn't being woken up in the night."

Isaac was due to start school in January but remained off until the week before February half term and he had settled in incredibly well, said mum. Sinead explained: "He is like a completely different child. He was a hundred miles an hour before but now he is a thousand miles an hour."

Isaac on a toy tractor
Isaac is now back to his happy self

Isaac had his last CT scan on February 1, five days before his baby brother Dylan was born. The scan was clear but he will still have regular check-ups and hopefully won't need anymore surgeries.

Sinead explained that Isaac absolutely doted on Dylan, and couldn't wait until he was big enough to play with him. The family are due to participate in the Noah's Ark Hospital Superhero 5k walk on June 30 and are fundraising to show their appreciation for the hospital. To support their fundraising efforts and make a donation, please click here.

"The nurses picked us up from the floor (literally) more than once and were there at all hours when we felt our world was falling apart with our little boy being so unwell," Sinead said. She added: "We cannot express how much happiness all the staff brought to Isaac when he needed it. Isaac’s interests were always taken into consideration during his recovery and the interaction from everyone no matter how busy really put a smile on his little face."

Isaac with his baby brother Dylan
Isaac with his baby brother Dylan

The goal of the Noah’s Ark Children's Hospital Charity is to create brighter todays and better tomorrows for the 73,000 children cared for at the Welsh children's hospital each year. The charity ensures that treatment and outcomes for children can continue to improve by funding new and innovative medical equipment and facilities.

Noah's Ark also strives to make the hospital a less frightening and more familiar place for children by sprinkling a little fun and happiness into hospital days.