PS. For the MacKay connection, the main source I consulted was the Book of MacKay by Angus MacKay, which contains a chapter on the Aberach MacKay coat of arms. Note also that according to a communication to the Gaelic Society of Inverness in the late 1800s, the MacKay Regiment carried the colours of Sir Donald MacKay when it Embarked for Europe in the 30 years war (1626). These were not the arms granted to MacKay a few years later when he was made Lord Reay.The colours must have been styled after the ancient Bratach Bhan of the MacKay, which hangs in the National Museum. The Keys arms bear some resemblance to these arms, as well as to those of Clan Lamont, and even possibly to the arms of the royal family of Sweden.