HUDDERSFIELD woman Shirley Green has vowed to fight until her dying day to free her sister from a lifelong jail term.
Shirley, 40, believes her sister, Julie Kenyon, was wrongly convicted of murder and has promised to clear her name.
Kenyon, 46, of Mixenden in Halifax, was jailed last July for killing her 89-year-old grandmother, Irene Waters.
Mrs Waters, of Albion Court in Halifax, died on December 5, 1996.
A post-mortem found that she died of natural causes as Mrs Waters suffered from emphysema, hardened arteries and chronic bronchitis.
But some of her relatives were suspicious and accused Kenyon of being responsible for her death.
Eventually, Kenyon's sister, Carol, secretly taped her confessing to the crime.
Their brother, David, gave police the tape in October, 2001, and Kenyon was arrested.
She said it was a mercy killing, saying she held her grandmother's hand while the elderly woman smothered herself with a pillow.
The trial was told by a medical expert that this theory was not credible. The jury agreed and found Kenyon guilty.
But new doubts have now emerged about the safety of the conviction and the independent Criminal Cases Review Commission is reviewing the case.
Shirley, who has always believed in her sister's innocence, is delighted.
The mother-of-four said: "I have said she was innocent from day one. Julie didn't want to talk publicly at first. But then she asked me to tell the world the truth.
"Now people have seen interviews I've done and are saying to me maybe she didn't do it.
"I'm going to prove she is innocent if it kills me. There's not a day goes by when I'm not wondering how to help her."
She added: "She didn't have a proper defence. It was all prosecution. Plus, Julie used to drink, she was on tablets and was depressed. She had been getting hassle from family. By the time she was in court she was confused and it went against her.
"But she is better now."
Shirley now has no contact with Carol, David or her mother, who all believed Kenyon was guilty.
Shirley said: "I was close to them before, but I didn't realise families could be so wicked.
"Me and Julie were never close, but I knew straightaway that she hadn't done anything. She wouldn't, because Nana was the only one who gave her the time of day."
Shirley visits her sister once a month in Durham Prison and they write regularly. But life is difficult. Shirley said: "It really gets me down.
It is a horrible feeling leaving her."