Here?s some probate files for the Greenan family:
Full Abstract :
Administration of the Estate of Henry Greenan late of Ballyweely County Down Farmer who died 1 January 1909 granted at Belfast to Mary Greenan Spinster
Full Abstract :
Letters of Administration of the personal estate of Mark Greenan late of Ballyweely County Down Farmer who died 23 August 1893 at same place were granted at Belfast to Patrick Doran of Rathland said County Labourer the Curator of the Minor Grandchildren (Limited). Effects ?70 3s. 9d.
Full Abstract :
The Will of William Greenan formerly of Bishop Auckland County Durham and late of Ballyweely County Down Farmer who died 22 March 1879 at Bishop Auckland was proved at Belfast by John M'Laughlan of Ballyweely Farmer one of the Executors. Effects ?21
The 1909 Probate file should be in PRONI, Belfast. (Not on-line yet). The 1893 file will have been destroyed in the 1922 fire in Dublin. The 1879 will is on-line on the PRONI site:
http://applications.proni.gov.uk/DCAL_PRONI_WillsCalendar/WillsSearchImage.aspx?id=184432
There were evidently several Greenan families on that townland. Griffiths has Peter Grennan on plot 13 in Ballyweely, in 1864. Alice Grennan lives next door on plot 12. She?s likely to have been a close relative, as is Henry Greenan on plot 11.
The revaluation records show Peter?s house changing to Catherine in 1901, and by 1923 the farmhouse was down, and only the land was in use, held by Henry Grennan/Greenan.
Catherine may have been Peter?s daughter. This is her in 1901:
http://www.census.nationalarchives.ie/pages/1901/Down/Clonduff/Ballyweeley/1248681
Here?s Henry in 1901:
http://www.census.nationalarchives.ie/pages/1901/Down/Clonduff/Ballyweeley/1248687/
Catherine in 1911:
http://www.census.nationalarchives.ie/pages/1911/Down/Clonduff/Ballyweely/257324/
The RC parish records for Clonduff only start in 1850 but you may find John and some of his siblings baptisms in them. A copy is held in PRONI.