Hello Ron, I have just searched my Melbourne General Cemetery disc and I see the graves of 20 HIGGINBOTHAM'S, sadly none with the given or middle name of Sarah.
The range of the deaths are form 1857 to 1982.
Some Notes on the history of the Melbourne General Cemetery
Melbourne's first cemetery was in what is now the Flagstaff Gardens. There were at least 10 burials there although there is some uncertainty about the names of those buried there. Only a single memorial remains of that burial ground.
The second Melbourne cemetery was located on what is now the site of the Queen Victoria Market, in 1837. The Gold Rush followed by the rapid growth of Melbourne quickly lead to this cemetery being filled and it was soon closed for new burials.
Although negotiations for what became The Melbourne General Cemetery were begun in 1848 it was not until 1852 that it was proclaimed. At that time it covered just 40 acres. Its area was later increased and it now covers 104 acres.
If I can be of any further help in checking this cemetery then do not hesitate in contacting me.