McGregor's Ardrishaig, Irvine, Tradeston, Glasgow

Robert McGregor was a merchant seaman who married Barbara Mackie on 28.02.1815 in Irvine, Ayrshire Scotland. Barbara was born in Irvine on 01.09.1794 but I do not believe Robert was a native of Irvine. We believe Robert may have come from Ardrishaig or Lochgoilhead. One of Robert and Barbara's sons was another Robert b 28.05.1830 in Dundonald. I can find no trace of Robert and presume that he either died prior to 1855 or that he left Scotland. Another of the sons was Adam b Irvine 8.12.15 who married Elizabeth McTaggart 4.8.1845 in Dundonald. Their son Adam McTaggart was born in Ardrossan 14.08.1857 - but I can find nothing between 1845 and 1857 for any other children. Again, did Adam the father, (another merchant seaman), leave Scotland for some time - I cannot find any notice of Adam the father's death either but know that by the time of Elizabeth's death in Tradeston, Glasgow 1873, Adam was already deceased. Any information on this family would be much appreciated - even if it is general info on the possible seafaring links between Irvine and Ardrishaig. Many thanks.