THE police have failed, football’s authorities have failed and most of all common sense has failed.

But one extraordinary three-year-old girl is succeeding where the adults haven’t by bringing a kind of peace to the most vicious rivalry in English football.

22 Brave Isla Caton needs £400,000 to get treatment for Neuroblastoma - and has had donations from West Ham and Millwall fans Credit: Supplied

22 The three-year-old needs treatment to treat a rare form of cancer that only affects 100 children a year in the UK Credit: Arfa Griffiths - The Sun

Ardent West Ham and Millwall fans have declared a surprise truce to help Isla Caton’s fight against cancer.

The hatred between these two hardcore East London clubs has gone beyond football tribalism.

The death of a Millwall fan in 1976 and a full scale riot last time the two teams met at Upton Park in 2009 is confirmation of a deep-seated animosity.

Toddler Isla comes from a family of diehard West Ham season ticket holders, passionate Hammers who bought into the blood feud like all the rest.

22 Tony Munday, right, has inspired fellow Millwall fans to raise thousands for Isla Credit: Supplied

22 Tony with a group of supporters outside a West Ham pub in Plaistow, East London Credit: Supplied

But her battle against cancer reached across the River Thames where Millwall supporters immediately put aside their mutual dislike of West Ham to rally behind her cause in a series of spontaneous and generous acts of charity that offer hope for Isla and for football as a whole.

West Ham fan and family friend Neil Taylor, 58, made the first move bridging the fierce divide to approach Millwall fans via social media.

Taylor said: “Millwall and West Ham fans are cut from the same cloth really, there’s just a lot of hatred there. I use social media for my Boleyn Days website. It’s proper old school stuff.

“Millwall do a lot for Help For Heroes and other charities, as do West Ham. I got to know a couple of people through that and I thought it would be really something if we could get Isla’s plight mentioned in one of their programmes. That would be a real touch.

22 Isla, whose form of cancer is not treatable in the UK, smiles with her mum Nicola Credit: Arfa Griffiths - The Sun

22 Tony raised money by running from The Den to the London Stadium Credit: Supplied

“When it did get in for the Barnsley match the response was terrific. We put it online and got about 800 responses. And not one of them was negative.

“Don’t get me wrong. I’m no Middle East peace envoy but it is amazing what’s come from this little girl’s battle.”

Isla has neuroblastoma - a particularly tough cancer to treat. She has already had a 22cm tumour removed from her tummy in a 10 1/2 hour op, 24 rounds of radiotherapy and 70 general anaesthetics. She is into her second stint of chemo.

When all that is done she needs to go to America for hi-tech antibody therapy which is designed to prevent the disease returning and is not yet available in the UK.

The bill could end up at around £700,000. West Ham fans have been "unbelievable", says Isla’s mum Nicola, but more astonishing is that so have Millwall’s, for whom she adds: “I don’t have the words to say how grateful I am.”

WHAT IS NEUROBLASTOMA? Neuroblastoma is a type of cancer that most commonly afflicts babies and young children. The disease develops from special nerve cells, known as neuroblasts, which get left behind from the child's development in the womb. It mostly begins in the sufferer's adrenal glands located above the kidneys but can occur in the nerve tissue that runs along the spinal cord in the neck, chest, abdomen or pelvis. The vicious illness can then spread to other organs like the bone, bone marrow, lymph nodes and skin. Neuroblastoma afflicts around 100 children a year in the UK but the cause of the disease is still not known. Symptoms can include: a swollen painful tummy, sometimes in association with constipation and difficulty passing urine

breathlessness and difficulty swallowing

a lump in the neck

blueish lumps in the skin and bruising, particularly around the eyes

weakness in the legs and an unsteady walk, with numbness in the lower body, constipation and difficulty passing urine

fatigue, loss of energy, pale skin, loss of appetite and weight loss

bone pain, a limp and general irritability

jerky eye and muscle movements

22 Efforts of fans have seen more than £300,000 raised - but more is needed Credit: Supplied

22 Isla has had a 22cm tumour removed, 24 rounds of radiotherapy and 70 general anasthetics Credit: Supplied

She said: “As West Ham fans, you just grow up hating Millwall. You don’t even ask why, it’s just how it is. I’m sure it’s the same for them too.

“But now we’re talking about grown men putting all that to one side for us. Millwall fans don’t like us but they have done all this for us.

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"I think true West Ham and Millwall fans have come together over this and I think a lot of them will stay in touch forever afterwards.

“West Ham fans have been brilliant too. As soon as Isla’s story got out they have been phenomenal. I was brought up in a working class house where we didn’t ask for anything. We don’t like asking now but we have to for our daughter’s sake.”

22 Millwall fan Jamie Pearce has raised funds by running the Brighton marathon in a West Ham kit Credit: Twitter/Jamie Pearce

22 Jamie, from Bromley, raised £1,500 for the run Credit: Twitter/Jamie Pearce

22 Isla, with skipper Mark Noble, was a mascot for West Ham's match with Bournemouth in January Credit: Getty Images - Getty

22 Millwall and West Ham fans have a long and bloody history of violence Credit: News Group Newspapers Ltd

22 A meeting between the teams in 2009 was marred by pitch invasions, violence and arrests - with one fan stabbed Credit: PA:Empics Sport

When West Ham last played Millwall it made international news for the scale of the trouble. An emergency call went out for extra police to race to stem widespread disorder that night in and around East London and there were three pitch invasions during the game.

Both clubs reserve a special venom for a game rated as C-plus by the cops – the highest risk of hooliganism. And it rarely fails to ignite.

The clubs may never be best friends but for now all thoughts are with Isla, who was West Ham’s mascot at their home game against Bournemouth earlier this season, carried in the arms of captain Mark Noble.

Former players - Carlton Cole, Matthew Etherington, Paul Konchesky and Jack Collison among them - are turning out for her this Sunday in a benefit match at Redbridge FC in Barkingside, Essex, to play a bunch of celebrities.

Tickets are available on the day or through her Facebook page.

22 More than 20 people were injured in the clashes, 80 people were arrested and West Ham banned 54 people for life Credit: News Group Newspapers Ltd

22 West Ham were also fined £115,000 for failing to control their supporters Credit: News Group Newspapers Ltd

New Den season ticket holder Jamie Pearce will feature in it, as a "reward" for defying vomiting, severe muscular pain and the humiliation of wearing a West Ham shirt to run the Brighton Marathon and raise more than £1,500 for the cause.

Jamie, 25, from Bromley, who works in HR, said: “When I was about 14 my school football team had a kit that was burgundy and blue – like West Ham’s. I refused to wear it and went in goal instead. That explains my feelings towards West Ham.

“But when I saw Isla’s story I felt compelled to do something. It’s more about somebody reaching out for help. If a family like theirs comes to Millwall looking for help then all jokes aside we have to do what we can.

22 Isla has been undergoing chemotherapy and radiotherapy for the past 15 months Credit: Supplied

22 Millwall fan Tony sits with West Ham fans at the London Stadium Credit: Supplied

22 Former West Ham striker Carlton Cole will be playing in a celebrity charity game this weekend Credit: Getty Images - Getty

“I guess the main reason I decided to wear the West Ham shirt was because I knew the impact it would have. Everybody who knows me knows how passionate I am about my club and so I knew it would generate interest.

“I was hoping to raise around £500 but currently we’re sitting at more than £1,500 and it’s helped to spread awareness.

“I’ve had a great reception and it really shows rivalry doesn’t exist where real matters, especially children, are concerned.

“If West Ham do get relegated this season then it would be interesting to see what happens between the fans should they play each other next year. I definitely feel something’s changed.

22 Isla's family are hoping she will be treated at a hospital in New York, if they can raise enough money Credit: Supplied

22 Isla, three, lives in Hornchurch, Essex Credit: Arfa Griffiths - The Sun

“There might still be a few idiots but I could walk into a West Ham pub and have a drink with them I reckon. I’d have to explain who I was first. Maybe I’m too optimistic but I think some of the stigma around this game has gone.”

Pearce joked: “Mind you, I’m missing Millwall’s last home game of the season against Villa to play in this poxy shirt again.”

Pearce admits he was inspired by the spirit of Millwall supporting cabbie Tony Munday, who lives in West Ham’s heartland in deepest Essex, near the Lakeside Shopping Centre.

Munday, 49, refused to be put off by bad weather when the Brentwood half marathon was cancelled and he chose to run from Millwall’s South London ground to West Ham’s London Stadium on the day of their Premier League home game against Southampton on March 31.

Brave Munday even diverted his route to stop off at the infamous Vic pub in Plaistow, a hardened Hammers boozer. He became the first Millwall fan ever to be bought a drink there.

He said: “I hate West Ham. I’m so anti-West Ham it’s unbelievable. And I’m a total wind-up. I’m a physical wreck but from time to time I do something like this and train for it. Isla gave me a reason. What better cause was there?

22 West Ham and Millwall have been bitter rivals for decades Credit: News Group Newspapers Ltd

22 Films like The Firm, with Gary Oldman, have spread the notoriety of the rivalry Credit: BBC Films

“When I offered to do it in a West Ham shirt the reaction was incredible. I’d raised £1,000 in 24 hours. One friend offered a grand there and then just to see me in the shirt.

“People talk about rivalries up and down the country but none is like ours. I have friends who support Sunderland and have been to the North East derby. People were walking along the streets together in different colours. That would never happen at West Ham vs Millwall. There is a feeling that eyes are on you everywhere.

“But as I ran past the Vic loads of old school West Ham came out to cheer me on. I stopped for a drink and carried on to the London Stadium. I sat in there and watched the game – the only person in the home end disappointed that they won 3-0 and then went back to the pub. I stayed there quite some time I can tell you.

“Let’s just say that some of the clientele in the Vic are ‘passionate’ about West Ham. I won’t name names. But I’ve been told I’m welcome back there any time and won’t ever have to buy a drink.

“I think some good is coming out of this as much for the fans as Isla. So many West Ham and Millwall fans are now in touch and I have hardly seen a cross word between them.”