Lily Willis, 8, from Great Lumley, County Durham, was diagnosed with a bone cancer tumour called osteosarcoma in February after she came home from school limping just weeks earlier.
The tumour, on her right leg, meant that her entire knee, tibia and part of her femur had to be removed and rebuilt with stainless steel adjustable bones.
As Lily grows, a magnet will be placed around her leg which will allow doctors to lengthen the bones in her shin and thigh as required.
Her mother Tori, 30, said: ‘Lily came home after school one day with a sore ankle. She had been doing cross-country and was limping. We thought nothing of it and imagined she had just sprained it while she had been out running.
‘But after a couple of weeks, the pain had travelled up her leg and didn’t seem to be going anywhere so I took her to the doctors.
‘I thought they were just going to strap her up and send her home again – we never thought it would ever be anything serious.
But Tori and Lily’s father Bryan were in for the shock of their lives after doctors sent Lily for an X-ray, which revealed she had a tumour on the bone above her right knee.
Bryan, 40, said: ‘They did an X-ray of her ankle and then called us back so they could do another on her hips.
‘We were told to wait five days and assumed this meant there was nothing serious going on or they would have done something straight away.
‘But the hospital called us a few days later and told us we had to take Lily out of school and get her there.
‘That’s when we started to worry. I could sense the urgency over the phone and I couldn’t possibly have expected what they were going to tell us.
‘I’d heard of children with leukaemia but for some reason I didn’t think of them as the same thing.’
Once Tori and Bryan had been told of Lily’s cancer, doctors sat the youngster down and explained to her what was wrong with her.
Lily said: ‘They told me I had cancer but I didn’t know what it meant. I’d heard people talking about it but I didn’t know what it was.’
Tori said: ‘When we were told Lily had the disease, I think my heart stopped for a second. My little girl had cancer. No parent should have to hear that.
‘I thought she was going to die. We asked doctors if she was going to be OK but it was a question they couldn’t answer – they just looked at us sympathetically.’
Just a week after her diagnosis in February, medics began Lily on a course of chemotherapy and performed a 14-hour operation on the youngster to remove her knee and tibia bones.
They then replaced them using adjustable stainless steel to act like real bones.
Bryan, a former mechanic, said: ‘Lily was so poorly. The chemotherapy hit her hard, she was sick a lot and had very little energy.
‘Her hair began to fall out which I think was hard for her – but now we can’t imagine her ever having any!
‘She also contracted pneumonia – a strain which doctors said was the worst they had seen, after her lung collapsed.
‘The operation was the hardest part. We didn’t think it would take that long so it was a waiting game for her to come out of theatre. The longer she was down there, the more we thought was going wrong.’
But the operation was a success and after installing Lily’s new limbs, surgeons managed to reconstruct all of the muscles, tendons and even blood vessels around the new bones.
As the new metal bones were too big for her leg when they were fitted, skin and tissue from her left thigh was used to stretch around her newly built limb.
Now that the cancerous tissue has been removed, Lily is well on the road to recovery.
She will still need up to six months worth of chemotherapy to ensure all cancerous cells have been destroyed before she can be given the all-clear.
Lily’s new bones will last until she is 14, when they will be replaced with adult sized metal pieces, which will be left inside her leg for the rest of her life.
In the meantime, her sisters Jessy, 5, and Ruby, 2, are pleased to have her home where they can help look after her with their parents, who both gave up their jobs to be Lily’s full-time carers.
The brave youngster has recently been nominated for a Champion Child of Courage award, after she made hundreds of friendship bracelets while she was in hospital to raise money for charity.
Her mother said: ‘She’s doing really well, she is better than she used to be. She is absolutely
‘It will be a while before Lily can walk independently as she has to build up the muscles again in her legs but she is doing brilliantly – we are all so proud of her.’