AS identical twin sisters, Emily and Kath Blunt have spent their entire lives together and shared every single experience. But at 20, they are facing being torn apart in the most heartbreaking way after one was diagnosed with a rare form of bone cancer and told she only has a few months to live.  Emily has been through 10 gruelling months of chemotherapy but is still expected to die within the year. She says the only thing keeping her going is knowing her twin, who is having sympathy pains mirroring her illness, will still be alive when she is gone. 'It is a great comfort to me to know Kath will carry on because she is part of me,' the 20-year-old said. A devastated Kath added: 'I have spent 20 years with a shadow and I can't imagine not arguing with, talking to or being with Emily. Part of me will be cut in two.' An X-ray revealed Emily had a 22cm-long tumour in her arm and by last August, specialists had diagnosed osteosarcoma - a rare form of primary bone cancer. Further tests showed it had already spread to her lungs and ribs and doctors predict she will survive less than a year. To help them cope, her family have thrown themselves into charity work to raise awareness about osteosarcoma. - Daily Mail They are also fundraising for the Bone Cancer Research Trust and might start visiting schools to talk to children about the condition. The twins' father Ian, who is currently working in Germany, is taking part in a big charity run there this month.