I have the following marriage record [courtesy of the Irish World Heritage Centre's database]:
Robert LIGGETT from Mullyrodden married Eliza IRWIN from Cranislough on 21st January 1851 at Upper Clonaneese Presbyterian Church.The Groom's father was named Robert Liggett and the bride's father was Robert Irwin. The witnesses were Robert Cousins and Isaac Johnston.
As Mullyrodden and Cranslough townlands are both in the Aughnacloy/Carnteel area I wonder if this family appears in your book?(There is also a Dickson connection as Robert & Eliza Liggett had a daughter who married a David Dickson in 1875).
I should be very happy to hear from you. Thank you for your time.