Hello Beth, More good news for you.I have been at the National Library today and looked at the Electoral Rolls,and found that Robert was at Pomona in 1913 and 1914,but not 1915,so the Robert PARKER dying in 1915 may very well be the correct Robert.
Amy Alice PARKER,daughter of Alexander PARKER and Ada Mary JACKSON died 24/3/1922(Reg.No.1922/00405).
Ada Mary JACKSON born 12/9/1879 in Queensland daughter of George JACKSON and Charlotte Ann CHILDS.
George JACKSON died 2/10/1927 (Reg.No.1927/B002611)son of James JACKSON and Mary HUTTON.
Charlotte Ann JACKSON(nee CHILDS)died 10/8/1926 (Reg.No.1926/B049684)daughter of James Richardson CHILDS and Jemima HOLDER.
Albert PARKER married Edith Augusta BEIN 27/10/1921(Reg.No.1921/B028799).
I think there may also be a daughter of Alexander PARKER and Ada Mary JACKSON born after 1919,because in the same electorate in 1939 there was an Ada Mary PARKER (JNR) and in 1939 an Ada Mary PARKER married an Edgar Charles PARRY on 16/9/1939(Reg.No.1939/B036605).
Albert Alexander PARKER married Elizabeth McKEOWN on 25/3/1939(Reg.No.1939/001863).
George William PARKER married Sylvia MANTTAN on 12/12/1936(Reg.No.1936/004325).
Albert Alexander PARKER and Elizabeth McKEOWN had a daughter die in Brisbane on 22/9/1942(Reg.1942/B058298).
Edith Augusta (BEIN)PARKER died between 1965 and 1967.
Albert PARKER died between 1982 and 1984.
George William PARKER's first wife Sylvia died between 1965 and 1967 and he then appears to have married a Brenda Joyce UNKNOWN.
If you E -Mail Mt.Thompson Crematorium,I would be fairly confident you will find Edith Augusta PARKER and Albert.
Ada Mary(JACKSON)PARKER does not appear in the death indexes between 1940 and 1964,but disappears from the Electoral Roll between 1941 and 1946.