In 1977 six-year-old Mary Boyle disappeared in Donegal.

Almost 38 years later Mary’s twin Ann told the Gardaí that she had been told on numerous occasions the identity of her sister's killer. In October 2015, Ann stood in front of TD’s in Leinster House and told them point blank she believed she knew who killed her sister and she believed there was political and garda interference in the case. Ann was supported by her cousin Margo O'Donnell, country singer, and sister of Daniel O'Donnell, who also claimed to have been told the name of the culprit. They hoped to spark a new investigation into the case. Little has been done in solving the case. Aidan Murray was a detective sergeant when Mary disappeared and spoke about the theory that a politician intervened in the investigation. "I only heard it in garda conferences but I could never prove that,” he said to The Independent. Investigative journalist Gemma O’Doherty was contacted by Ann to investigate the case. Gemma has since conducted interviews with retired gardaí and those who knew Mary. Slowly she is attempting to piece together the moments that led to Mary’s disappearance. Speaking to Newstalk Gemma said: "Mary was visiting her grandparents, extremely remote farm outside Ballyshannon, just four miles from the border with Fermanagh. "This part of the country was one of the most heavily policed at the time. There were at least three permanent Garda checkpoints operating 24/7 because this was the height of the Troubles in Northen Ireland and on the northern side, the RUC, and the British Army had a number of units there, which were operating permanently "Really people need to know the landscape that we're talking about, the nearest road was a long distance away.” Gemma, like many, believes the case is being deliberately covered up. "We should be thinking about Mary Boyle who is our youngest missing citizen. "I believe, so does Ann and a number of officers, that she was brutally raped before her murder. "We also believe that her rapist and murderer is still at large in this country and is a danger to other children and that is what is key about this case.” On Tuesday Gemma, Ann and Margo met with Micheál Martin and presented “evidence” that a politician was involved in the cover-up. According to The Irish Times, Ann was told by Mr. Martin to take her concerns to the Gardaí. “But we have no faith in the Garda. You wonder what you have to do to get justice in this country,” she said. https://www.youtube.com/watch?v=LtN19gKGY1Y