'Stay happy': Girl's journey from cancer ward to live TV

In many ways, Blathnaid is a typical 12-year-old, who enjoys hanging around in the park with her friends, loves music and is learning to play the piano and guitar.

She is animated, chatty, confident and full of life, despite having just completed two and a half years of intensive chemotherapy and almost losing her life – twice.

Blathnaid was diagnosed with T-cell acute lymphoblastic leukaemia, an aggressive blood cancer, aged nine. She has been supported along a life-changing journey by the cancer charity Pasic, which receives funding from Children in Need.

Now, she is preparing to take part in the Children in Need choir on national television.

Blathnaid, who lives near Sleaford, Lincolnshire, first noticed symptoms during an Easter Egg hunt.

"I couldn't walk half a mile to get all these Easter eggs and I thought, oh, OK. I had to sit down and I even threw up," she recalled.

Initially, her mother, Dara, thought it was a chest infection, but when they went to the GP, Blathnaid was sent straight to A&E.

"It was just panic, pure panic," Dara said.

Blathnaid was transferred to Queen's Medical Centre, in Nottingham, where she underwent emergency surgery.

"She wasn't able to breathe, she wasn't able to lie down, her lungs had filled up with fluid," said Dara.

The operation lasted eight hours and involved putting chest drains into Blathnaid's lungs while she was sitting up, conscious and talking to the surgeon.

Blathnaid's dad Glynn recalled how life was put on hold, their futures in the hands of medical professionals. Work had to stop, bosses had to be understanding.

"There were a few big operations where Dara and I had been called back to the hospital after being sent home, but staff wouldn't tell us why and we did think, she'd passed away," he said. "It was awful, absolutely awful."

On one occasion, when they got to the hospital, Blathnaid had been put into a coma.

"I used to go outside the hospital and I would cry my eyes out, uncontrollably, because you didn't know what was happening. Just all thoughts going through your head, driving to work and seeing older children going to school and thinking, 'gosh my child may never get to that age'," Glynn added.

T-cell acute lymphoblastic leukaemia affects the development of white blood cells in the bone marrow that help the body to fight off infections.

It is estimated there are about 60 cases of this type of leukaemia per year in the UK affecting children and adults.

According to the Leukaemia Research Foundation, childhood onset occurs at about the age of nine and adult onset at about 30, with 75% of children and around 60% of adults remaining cancer free after five and three years respectively.

As Blathnaid has found, treatment can be intense and takes a number of years.

She was treated with chemotherapy, taken orally and through lumber punctures into her spine to protect her brain, as well as through a central line in her chest.

She also became very ill after an infection that started with mouth ulcers and spread through her digestive system, causing typhlitis, colitis, mucositis, hepatitis, sepsis and then pneumonia.

"It just went on and on" said Dara. "She was in and out of consciousness for about six weeks".

That was the second time her parents thought they might lose her.

Blathnaid missed two years of school.

"I felt really left out because I couldn't go out and play, I had to learn how to walk again and I felt really bad making all of my friends have to come and see me," she said. "I just felt really isolated."

Despite this, she managed to catch up with her education and pass her 11-plus exams.

The cancer charity Pasic helps both the child and parents by providing emotional support and counselling, financial support and trips and activities for the families.

Children in Need has been supporting Pasic for the past 10 years, with the most recent grant totalling almost £88,000 over three years, according to the charity.

Glynn said: "It's only when you're in this situation that you realise what these charities do. Pasic came in to see us and were just there for you."

Blathnaid said the charity's social workers were "fantastic", whether by cheering up the family in hospital or taking them on trips to places such as Alton Towers.

Blathnaid has been practising for months to take part in the Children in Need choir, often by video with other participants, with a final rehearsal at the BBC studios in Salford.

Glynn said it had been funny to watch her "howl" in the conservatory at a computer screen, but added: "I think they've all formed a real bond, they'll have a great time when they see each other."

Dara said: "We're so looking forward to it – we're so incredibly proud of Blathnaid."

Blathnaid said: "It'll be a bit nerve-wracking at first, but I'll get to meet all these people that I've been singing with on the computer in real life and I'm really excited about that".

When asked what advice she would give to other children going through what she has, she said: "You can never be glass half-empty, you always have to be optimistic about everything – just stay happy all the way through, that's what I did and it does get better... eventually."

Children in Need will be broadcast on BBC One and iPlayer from 7pm

Listen to highlights from Lincolnshire on BBC Sounds, watch the latest episode of Look North.

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