Louisa, Don't know if this helps, but in my search for a Margaret Pyper, I was given info on the siblings of a William Pyper, b. 28 May/1794: Margaret, twin sister Annie, James, David, George, Mary, and John. When I looked in the IGI website for a Margaret Pyper born about 1790, it came up:
Margaret Pyper, christened 18 March, 1790, Saint Cyrus, Kincardine. Father: David Pyper, Mother: Catherine Smith. Haven't been able to confirm if this is my Margaret, but thought I'd pass the info along to you.