Thanks both for noting this. I see in the 1911 Census they are correctly identified by country of birth, although Edward's birth area is recorded as 'Cudbrig' which I can't find. It could have been a mis-heard 'Kirkcudbright', except that (a) the 1911 census was completed by the head of household themself, not spoken to an enumerator; and (b), Kirkcudbright is nowhere near Coatbridge.