In 1862 Mary SULLIVAN born 1842 in Tipperary Ireland married David William FINDLAY born 1826 Scotland. Married in Ballarat.
They had a tribe of children mainly around Ballarat, Mary, Margaret, David, Thomas, Euphemia, Francis.
Frederick, David and Charles were born in Echuca.
David FINDLAY remarried in 1891 to Catherine Mary HICKEY.
Where did Mary go? A half dozen trees in ancestry have her death as 1891 in Ballarat, there is no evidence that I can see for this apart from the fact that David remarries in 1891.
Ballarat Cemetery records don't show her, BDM records don't show her, no probate.
The only thing I can think of is a divorce and remarry but I can't find any evidence of that either. Nothing in Trove as far as I can see.