There is a lovely photo of Norman Clarence PIPER here

http://cas.awm.gov.au/photograph/P07357.001

Father John Thos Arthur PIPER died in 1923, aged 52, in Melbourne East, Victoria, son of Thos PIPER and Ellen WORDSWORTH (reg 6835).

Mother Florence Victoria PIPER died in 1929, aged 57, daughter of John AULD & Sarah McCORKLE (reg 1312).

From NLA Trove, her death notice:

The Argus, Wednesday 16 January 1929
PIPER.-On the 15th January, at her residence, 210 Nicholson street, Fitzroy, Florence Victoria, relict of the late John Thomas Piper, and loving mother of Violet, Stanley, George, Leslie, Vera (Mrs. Peterson), Norman, Olive, Gordon, Reginald, Roy, and Edna.

Some chn missing from online trees so will post all here, let me know if you want reg no's

Chn (all born Fitzroy South):
John Thos 1895, d. 1895 aged 8 days
Violet Ethel 1896, d. 1970
Arthur Nicholson 1897, d. 1899 aged 1
Stanley 1899, d. 1962 [as Stanley Livingst]
Wm Geo 1900, d. 1961
Leslie Jno 1901, d. 1975
Vera May 1905
Norman Clarence 1906, d. 1944 [Qld]
Olive Pearline 1908, d. 1976 [as Olive Pearleen]
Gordon Raymond 1909, d. 1964
Reginald Bernard 1911, d. 1981
Roy Ashton 1912
Edna Florence 1917

WWII enlistments
PIPER GORDON RAYMOND : Service Number - 55272 : Date of birth - 14 May 1909 : Place of birth - FITZROY VIC : Place of enlistment - MELBOURNE : Next of Kin - PIPER MARY
PIPER NORMAN CLARENCE : Service Number - VX105096 : Date of birth - 28 Jun 1906 : Place of birth - FITZROY VIC : Place of enlistment - TAMWORTH NSW : Next of Kin - PIPER LORNA
PIPER REGINALD BERNARD : Service Number - V335687 : Date of birth - 10 Apr 1911 : Place of birth - MEL VIC : Place of enlistment - WESTGARTH VIC : Next of Kin - PIPER BEATRICE
PIPER Roy Aston - [Civil Constructional Corps - Victoria] number CV26238 - Year of birth 1918

Norman & Roy's are digitised so you can read them online

Do you need marriages for the above siblings?