Re Samuel, the Sydney Morning Herald 19 Feb 1880 has a funeral announcement. Is it for your Samuel? It does not make any mention by name of his immediate family... It mentions that the funeral was to move from the residence of Mrs Stacy, Albert St Paddington to Waverley Cemetery.
Back in 1841, the immigration papers per the Helen, departing Liverpool, England, for Samuel and Jane Fisher give details about their parents. That info can be helpful when checking for deaths in NSW.
Samuel was son of James FISHER and Ann BRADLEY, he was aged 28, and a Presbyterian. Jane FISHER, his wife aged 25, was the daughter of John MCBRIDE and Sarah HOOD, oops ADD and a Presbyterian....
The NSW bdm online index has the 1880 death registration for Samuel FISHER with parents as James and Ann registered Paddington #3773, with date of 17 February.
so the informant knew the names of Samuels parents. The informant may have known other information recorded on the d.c, including his marriage to Jane. It may even note her as deceased, although it was not a formal requirement to note if the spouse was then living.
I think the Mrs STACY of Albert St was likely Sarah A STACEY, nee FISHER, who was married in 1872.
Likely you have much of the above, but it can be sensible to share with the regulars on the Australia Board to give background.
JM