Hi Kelly-Paul,
Welcome to rootschat

I can't see a marriage for the couple on W.A. BDM
http://www.bdm.dotag.wa.gov.au/ I have only found the birth of Charles so far
1885 KELLY Charles Brackell, father Mark, mother Mary Jane BATT, at Upper Gasgoyne reg 26414
The middle-name of Brackell maybe a good clue about ancestors.
Where is the sandstone area of WA (excuse my ignorance

), is that Upper Gasgoyne?
And is Manilya Station in WA? In Upper Gasgoyne?
Do you know when and where Mark and Mary died? Perhaps we can find an obit which tells us more about their background.
If all else fails it would be worth buying the birth certificate for Charles Brackell KELLY as it should list where parents are born married etc
regards,
Ros
correction : Here's what to expect on a birth cert of that year in W.A.
http://www.jaunay.com/bdm.htmlSo it is only after 1896 that most info is given.