• Married: 9 Mar 1893, Redfern, Sydney, N.S.W., Australia ^{1 2}
• Died: Before 1923

  Marriage Information:

William married Ida Winstanley, daughter of Robert Winstanley and Mary Ann McSorley, on 9 Mar 1893 in Redfern, Sydney, N.S.W., Australia ^{1 2}. (Ida Winstanley was born on 13 Jan 1865 in York-street, Sydney, New South Wales, Australia ^{3 4}, died on 26 Dec 1923 in Natal, Penkivil-street, Willoughby, Sydney, N.S.W., Australia ^{5 6} and was buried in Waverley Cemetery, Sydney, N.S.W., Australia.)

  Marriage Notes:

"ROBERTSON - WINSTANLEY .—March 9, at Redfern by the Rev. Robert Inglis, M.A., William Robertson to Ida Winstanley."