James Beattie married Elizabeth Vaughan on 7 August 1858 in Killyleagh 1st Presbyterian Church, both were full age (you can see a digitised image of an extract of the original certificate via the GRONI website, it is pay to view). Bachelor James was a labourer living in the townland of Barnamaghery, the son of William Beattie, a weaver. There's no guarantee his residence at the time of marriage was long term, however Griffith's Valuation shows a house in Barnamaghery occupied by a William Beatty (print date for that area was 1863), so just a possibility. Spinster Elizabeth was living in 'Killyleagh Mills', the daughter of David Vaughan, a labourer. The witnesses to the marriage were Samuel Jamison and George Vaughan. A George Vaughan married a Mary Graham in Killyleagh Presbyterian Church on 1 August 1859, his father was also called David, so just a chance he was a brother.
Tracking further back, eg. to when and where James and Elizabeth were born, may prove problematic, you are back to an era pre civil registration when church / other records and the information within them were scant.
