Am a bit new to this, so please accept my apologies if I am making fundamental mistakes.
Am researching William Campbell and have found a marriage to Janet Hart on 14 March 1800 Gorbals. The OPR certificate just states "William Campbell an Janet Hart both of this parish, married by the Rev James McLean 14 March 1800". No parents, witness names, addresses, or ages etc..
Have also found two births for Janet Hart 16 Nov 1777 and 4 Jun 1780 to Archibald Hart/Mary Anderson, Gorbals. Both OPR certificates state "Archibald Hart, weaver, in Gorbals had a daughter Bxxx (bought?) forth by his wife Mary Anderson upon the 31st and baptised the 4 June named Janet". The other birth certificate has the same level of information. I assume the Janet 16 Nov 1777 died, although no death/burial record can be found.
The questions/queries I have are:-
1). Will there be other records that have additional information to the OPR certificates?
2). How can I be sure that the two births are really from the same parents and not two different couples with the same name?
3). Without a death, how do I know which of the births is the one that married William Campbell?
4). How can I be sure that the William Campbell/Janet Hart I am looking for, are this couple as there are no parent names etc. on the OPR certificate/record?
Any assistance is appreciated - and when one gets to the 1700/1800 is this the norm for the level of information available, if so how does one go back further, with probably less clarity from official documents, without getting the wrong ancestors?
Thanks in advance for views