Hi Sam
As you have seen, the Scottish Statutory BMD indexes work differently to the English ones. For births, as you are finding, they only show year of birth (not quarters like the English entries) and mother's maiden name is not given (unlike English index entries post 1911).
Certificates for the period you are in are available to order from the GROS via Scotlands People (£10GB per extract). Alternatively, if you knew someone visiting one of the main Registry Offices, this information is available to view on line there for more recent certificates. Perhaps also if a RChatter is visiting any of these centres, they could look this info up for you.
In your position, at this stage, I would take it stage by stage. Firstly, I would order via SP that marriage certificate that you have found as I assume you are certain about bride/groom's names and dates. Scottish marriage certs. have more information that English ones and will include full details on parents' names, including mother's maiden name, occupation for father, and whether either of them were alive or deceased at the time. With the information confirmed regarding Thomas/Patrick's parents, you can then go about searching for his birth which will contain his parents' names and let you verify it is the correct one. Again, this would require a personal look up or you could ask the GROS to conduct a search to find his birth for the year (+/-3 years) that you believe was his birth and with the names of parents you have confirmed from the marriage cert. They will have specific charges for this which you can enquire about.
Monica
Added: Sorry Sancti, didn't get the red warning on a previous post. I think there is a problem at the moment with that notification
