Hello
From the 1881 census:
Allan House Newton St Blairgowrie, Perth
George S. Duncan Head Marr 69 Accountant b Glenbervie, Kincardine
Margaret Duncan wife 49 b Monievaird, Perth
William J. Duncan son 19 Bank Clerk b New York (British Subject), United States
Arthur D. Duncan son 14 scholar b New York (British Subject), United States
Elizabeth D. Duncan daughter 12 scholar b Braco, Perth
Helen S. Duncan daughter 8 b Newtyle, Forfar
Regards, Steve

PS also found a Frederick G Drummond earlier - a grocers assistant born Philidelphia - and now can't find him - a boarder in Lanarkshire?