Hi Perri,
I am in Oz and had a quick look on trove. The death notices I can find don't mention any other family but I will look a bit further. He died on the 3rd of September 1879 and this is a report from the SA Register 29th August 1879. It looks like he died as a result of this accident.
Accident to Mr. B. GRAY, J.P.— An accident occurred to Mr. Benjamin Gray, J.P., brewer, of Blakiston, on Wednesday, August 27, which but for immediate assistance mast have terminated fatally. Mr. Gray was crossing a platform in his brewery immediately above a large vat containing several feet of water, which was nearly at boiling heat, when a part of the wood work of the platform gave way, and he was precipitated into the vat beneath. Mr. Gray was fortunately able to cling to a beam, by which he managed to keep hia body out of the hot water, but bis feet and legs as far up as the knees were severely scalded. One of his men, who happened to be close at hand, released him from his perilous position. Dr. Weld was in immediate attendance.
Cheers
mabeljessie