Hi,
I have had a quick look on the NSW BDM website and as per usual for marriages BEFORE civil registration commenced, there's two records of the 1848 marriage for Fancis and Bridget. One event, two different index references. Sorry if I am getting too specific but ....
This is because of the NSW government's then requirement that a record of each baptism, burial and wedding was to be transmitted to the NSW Chaplains. This requirement dates back to the era of Governor Macquarie (1810-1821). So, what is on ONE record can often be slightly different from what is on the OTHER record.
1848 marriage
Volume 73B line 1642
and
Volume 78, line 765
which of the above references is the document's reference please.
However, in either instance, it is unlikely to learn the names of the parents of either the bride or groom from those records. If either the bride or groom were not yet 21 years of age (ie classified legally as an 'infant' in 19thC or as a 'minor' in early 20thC until turning 21) then the name of the person (and relationship) giving consent is recorded on the mc.
Cheers, JM