Beaming with delight, Daisy Wigginton tenderly cradles her baby sister Willow and sings ‘Twinkle, Twinkle, Little Star’ to her.

Determined to watch her tiny sibling grow up, the brave four-year-old refuses to let the cancer that is ravaging her body beat her.

Despite feeling utterly drained and exhausted from her gruelling hospital treatment, her eyes light up every time she sees Willow.

It spurs her on to fight against her disease, which she was diagnosed with in November after developing a ‘Darth Vader-like’ cough.

Daisy’s mum, Ria, from Chichester, Sussex, said her young daughter greatly enjoys being a “big sister” to three-month-old Willow.

The 33-year-old said: “Willow is definitely the motivation for Daisy to fight the cancer. She wants to be a true big sister to her.”

Daisy was diagnosed with Lymphoblastic Lymphoma around three months ago after her concerned mum took her to the GP four times.

Ria says she was initially told her daughter had a lower chest infection – before the poorly youngster was diagnosed with asthma.

Daisy was prescribed steroids and inhalers, but when she didn’t show any signs of improvement, her mum took her to Chichester A&E.

There, an x-ray revealed a tumour in her right lung.

The following day, Daisy was transferred to Southampton General Hospital.

After further tests, oncologists told her devastated parents that she had an aggressive and advanced form of the cancer.

She was found to also have tumours in her kidney and spleen.

The youngster was immediately started on chemotherapy, and will need treatment for another two and a half years to fight the condition.

She had to spend Christmas and New Year in hospital, as well as her fourth birthday last week. But remarkably, she didn’t ever complain.

Mum-of-three Ria, who is still on maternity leave as an adult care worker, said: “Daisy has never complained once. Instead, she battles through and is full of smiles when we bring her sisters to visit.

“She adores Willow and wants to show her how to play with dollies and say her first words. She is determined to fight this condition so she can be the big sister she always wanted to be.”

She added: “Daisy was so excited when she discovered I was having another baby and couldn’t wait for Willow to be born.

“She and her big sister, Primrose, five, cooed over her, sang nursery rhymes and would help me bathe her.

“But our perfect bubble of happiness was cut short within a month. Instead, I had a tiny baby and a little girl fighting for her life.”

While Daisy is in hospital, Ria and her 43-year-old husband, Darren, are taking it in turns to be by their daughter’s side.

Ria said: “Daisy is currently fighting an infection and quite poorly.

“Because the hospital is a 90-minute drive, we take it in turns to be with Daisy, so one of us can always be with her and the other with Primrose and Willow.

“We are literally like passing ships.

“Primrose also really misses her little sister. There is only 16 months between them and they have always been incredibly close.

“They have done everything together and, until now, barely left one another’s side, so it’s very hard for them both.”

She added that Primrose worries about Daisy constantly – particularly now the little girl has lost her beloved hair.

“She knows how much Daisy adored her hair and loved playing with it and making it look pretty,” said Ria.

“It’s upset Daisy too – she’s always wanted to look like a little princess and is frightened she will now look like a boy.

“It’s heart breaking as a parent to see your child worry like that.

“But the Little Princess Trust have kindly made a wig for Daisy, virtually identical to how her hair used to look, so she is very excited about that.”

Daisy’s illness has meant that Darren has had to give up his job in the construction industry to help Ria care for their three daughters.

It has left the family in a worrying financial predicament, and they have launched a GoFundMe campaign to try and help them through.

Ria said: “With no income coming in, we will struggle to pay the bills and the rent, or provide for our children. But we have no option.

“One of us needs to be at the hospital with Daisy and the other at home with Primrose and Willow, who is just three months old.

“Our main concern is obviously Daisy – she needs us more than ever now.

“But we are realistic that our money is running out fast and it’s just awful that we have to worry about that too.

“We are so grateful to everyone who is helping us – it means so much and we can never thank them enough.

“Seeing how kind people are really restores your faith in human nature.”