Hi MaryF
...and welcome to Talking Scot
Have you searched for a marriage for Alexander Ralston maybe possibly in the same area as the births and a year or two before?
There are a three mentions on IGI of a possible candidate, but they are all submissions (and seems odd there is no child called Christian/Christina if this is the case:
ALEXANDER RALSTON
Spouse: CHRISTIAN FREEBAIRN
Marriage: 22 JUN 1755 Glasgow, Lanark, Scotland
A parent search for the above couple seems to bring up a few more kids: e.g. Margaret 1759, James 1766, Christian 1768 and one or two more, but as the dates appear to overlap with the ones given above, maybe this is not your couple.
- have you have already traced this Alexander and he is not your man?
Best wishes
Lesley