Ancestors or Descendants McGahey / Megaghey

I am looking for the ancestors and descendants of Richard McGahey (c1824-1912) and Elizabeth McGahey(nee Morgan) (c1830-1904).

Their children were John (1865-1940), Robert (1866-1949), Matilda (1868-1948), Richard (b 1870), Charles (b 1872), Sarah Anne (b 1874), Isabella (b 1876). All were born in the district of Irvinstown.

John, Robert and Matilda emigrated to Australia in late 1880's and Isabella to America.

There are various spellings for McGahey, Megaghey, Magaghey, Magahey, McGahy.

Any clues would be much appreciated.

Thanks

Anne Hesp