My Doodys also came from Kildare. There were only 5 Doody famiies in the early Castledermot Parish Registers, and they were probably related as they were sponsors for each other's children. Here is information on your branch.
James Doody of Killelan married Bridget Flood. Known children:
1. William Doody
2. Michael Doodyborn 7 May 1793
1. William Doody of Timolin, County Kildare, married Mary Kelly 3 November 1820.
A. James Doody born 15 November 1822
B. Bridget Doody
(Scully’s 1840 census Timolin: William Doody, son- James, daughter-Biddy)
(Giriffith Valuation 1852, Village of Timolin, number on map:30, occupier-William Doody; Landlord-John Masterson, description of tenement: house)
A. James Doody married Mary Timmons 27 November 1858
(according to the Mullaghmast Diaries “James Doody, Timolin died in December 1896.)
Children of James Doody and Mary Timmons:
a. William Doody born 2 March 1859
b. Christopher Doody born 30 September 1860 (Sponsors: John Hipwell, Anne Byrne)
c. Jeremiah Doody born 12 January 1862
d. Margaret Doody born 8 November 1863
The five Doody families in the early Castledermot Parish Registers:
James Doody of Killelan and his wife Bridget Flood and family; Andrew Doody of Simonstown and his wife Anne Connor and family; William Doody of Sheriffs Hill and his wife Alice Nolan and family; Thomas Doody of St. Johns and his wife Mary Cleary and family; (this is my branch) Christopher Doody of ? and his wife Rosa Heyden.
Sources: Castledermot, County Kildare Parish Registers, Tithe Applotment Books, Scully’s Census, Giffiths Valuation, the Kelly and Mullaghmast Diaries, Headstone inscriptions and Electoral Registers.