Not related but hope this may add to your research. From NLA Trove newspaper site:
The Sydney Morning Herald, Thursday 24 January 1952 BENN, George.-January 23, 1952 of Railway Street, South Woy Woy, formerly of Sutherland and Blackheath, beloved husband of Blanche Margaret and loved father of Doris, George, Pearl, Grace, Olive, Hazel, Fred, Lorna, Rose and Sylvia, aged 64 years.
He was interred at Point Clare Cemetery; Blanche died in 1966 aged 76, daughter of Hy & Amelia. Headstone photo here: austcemindex.com/cemetery-inscriptions.php?id=505
George's father Thomas died in Redfern NSW in 1912, shown by this memorial notice by George & Blanche the following year: Wednesday 8 October 1913 BENN.—In loving memory of our dear father who departed this life, October 8, 1912. ... Inserted by his loving son and daughter George and Blanche Benn.
There are also notices from his wife E. Benn (Elizabeth), son F. Benn (Fredrick, d. 1940), daughter Elora (Peterson), and son H. Benn (Harry, d. 1944).
Thomas' death reg (18426) shows his father's name was John. His wife Elizabeth died in Redfern district ('Halifax', Alfred St, Mascot) in 1925, aged 70 (reg 10277). She was buried at Church of England Cemetery, Botany.
Here is a brother of George: Tuesday 4 October 1932 BENN-October 2, 1932, at the Coast Hospital, in his 51st year, John Willie Benn, beloved brother of May and Harry Gates, of Auburn, and third son of the late Thomas and Elizabeth Benn, late of Mascot.