Robert Lunn and his family lived at No. 4 from 1896 until after 1901. He was a plumber and gasfitter, with business premises at 3 Deanhaugh Street. Robert Hume Lunn was born about 1855 in Edinburgh, son of James Lunn, an auctioneer’s porter, and Mary McDougall. He died at Portobello on 29 January 1938.
Robert Lunn married Mary Anne Courtneidge (1857-1944) on 25 April 1879. They had at least eight children, including two born at No. 4 Malta Terrace: John Thompson Lunn (1897-1967) and Mary Anne (1900- ). In 1901, two sons Robert (1880- ) and Charles (1882- ) were also plumbers, probably working with their father.