Hi Matthew, Great to hear from you. The research in County Mayo was initiated by a distant cousin of mine (and presumably she's an even more distant cousin of yours!) who was visiting Westport a few years ago. There was a two page report provided for a fee.Some of the information doesn't match my own research. This report has the only mention of William and Ann Brewster I have seen to date. I would be happy to send you a digital copy of the report.
Did your Robert remain in Ireland? Are you aware of Alexander or any of his siblings I mentioned in the earlier post? Are you aware of any current Brewster family residing in County Mayo, in Ireland or elsewhere (besides me...)? Best regards, Patrick Green