Thank you everyone. I did buy the death certificate on Groni in which her son Wm. J. Adams was present at death, his residence Ballynease. Also bought the death certificate of her daughter Sarah Maria in 1945 at which R. Millar was present which would be the son of her sister Margaret since the father R. Millar died in 1928. Proves to me that Margaret married Robert Millar, which I thought, despite many online trees saying that Margaret married John Black.
Thanks again, everyone. Peggy