Hello.
My mum was Mary Jamieson born in Waterside and lived in Eglinton. Her mother was Margaret English, her father William Jamieson. Margaret had three other children, Margaret, Anne and William. William Jamieson was a quarryman and worked in Scotland. Margaret died during childbirth and Mary, Anne and William were brought up by the Duddy family in Eglinton. Does this link in anywhere with your findings? I've never been able to find out much on the family. Best wishes, Marie.