The furthest back (with documentary proof) is John GILLIES who married Jane TAYLOR (born abt. 1800)

Their son, Robert GILLIES(1829-1906) married Margaret JARVIE.

Helen GILLIES was the child of Robert GILLIES (1829-1906) and Margaret JARVIE. Other children of Robert GILLIES and Margaret JARVIE were Agnes Dobbie Gillies(1852-1953); Robert Jarvie GILLIES(1886-1944) 

Helen GILLIES (1881-1951)  married Peter ERSKINE and they lived at Castlecary Mill, Stirlingshire.

William ERSKINE (1911 – 1983) born to Peter ERSKINE(1876-1939) and Helen GILLIES (1881-1951).