Margeret Lawton's family claim they had to watch helplessly as the 91-year-old was ignored for two hours and left untreated until she stopped breathing. The family say they told medical staff that Margaret suffered from acid reflux, and needed to take the over the counter antacid Gaviscon after meals. But they say that they were shocked when a nurse at Barnsley Hostpital, South Yorks., refused to give Margaret more than two "thimble-sized" amounts of the antacid, even though they could see she was having a severe attack. Margeret died on Sunday July 23, but her grieving family have refused to collect the death certificate, which they say lists "non-lethal" causes of death, and have demanded a post mortem. While the death certificate doesn't list acid reflux as a cause of death, the family are hoping that the post mortem will show fluid in her lungs as a result of the acid reflux attack. Margaret was admitted to Barnsley Hospital on Friday July 21 after becoming confused and unsteady on her feet. Son-in-law Terry Thornton, 63, explained: "She had lived here with us for over a year, but the doctor diagnosed her with Charles Bonnet Syndrome, which meant that she was basically seeing things that weren't there. "It isn't life threatening in any way. "She was also suffering from very slight acid reflux and mild thyroid issues, but her GP made it clear that these were nothing to worry about. "He sent her into the hospital because of her confusion." Daughter Christine Thornton explained that the family told hospital staff about Margaret's acid reflux and that she needed Gaviscon after her meals. But when Terry and Christine returned to visit Margaret on Sunday July 23, they say it was clear than she needed urgent medical attention. Retired structural engineer Terry said: "Immediately I knew there was something wrong. She was coughing up violent acid into a tissue and struggling." Christine said: "I called for help, and said she's having an acid reflux attack. "I had to ask a nurse twice to get some Gaviscon, and when he eventually came back he only had a tiny thimble with him. "We told him that wouldn't be enough but came back with the same sized amount. "Then he said that she couldn't have anymore because it hadn't been prescribed by a doctor." After watching her suffer for another 15 minutes, Terry said he ran to a local shop to pick some Gaviscon up himself. Terry said: "When I walked back in she stopped breathing. "Suddenly doctors and nurses appeared and we were asked to move to a small room while they tried to revive her. "About 45 minutes later two doctors came in and asked us about her symptoms and complaints. "We explained about the Charles Bonnet syndrome, her Thyroid issues and the mild acid reflux. They hadn't heard of the Charles Bonnet syndrome before. "Christine wanted to stay by her bed until the end, so I went back home to feed our four cats. "By the time I got back she had died." The family have since refused to collect Margaret's death certificate. Retired legal secretary Christine said: "It said that the causes of death were old age and contributory factors, thyroid problems and Charles Bonnay Syndrome. "As far as we're concerned none of the things they listed were life threatening, so we refused to accept it." A post mortem is currently being carried out on Margaret's body, with the results expected in a few weeks time. Terry said: "If I hadn't have been there myself then I wouldn't have believed it. "We were surrounded by doctors and nurses and she was in severe distress and pain and no one would do anything." Christine said: "If someone had come and tried to help her with the same results then I would have accepted that. "I was so incensed because that certificate was a slur on my mother's memory and an insult to her." Terry has submitted a formal complaint to Barnsley Hospital NHS Foundation Trust, but the family has yet to have any reply. A spokesman for Barnsley Hospital said: "We offer our sincere condolences to the family and friends of Margaret Lawton at this difficult time. "The family has raised some concerns with us and we are in the process of liaising with them to discuss the points they have raised and answer any questions they may have."