If you do a search for a male Neff born in Kentucky you only get a few names:
Valentum Henricum Neff 01 Jan 1863 Twelve Mile Creek, Campbell, Kentucky, USA - 1944
Adamus Joannis Neff 12 Sep 1866 Twelve Mile Creek, Campbell, Kentucky, USA -
William Chester Neff 09 Jan 1896 Harlan, Kentucky, United States - 16 Jul 1918
Abraham Neff 07 Jun 1818 Kentucky, United States - 18 Nov 1906
Willis G. Neff 30 Aug 1830 Boyle County, Kentucky - 21 Jan 1898
Michael Renaye Neff 23 Mar 1952 Liberty, Casey, Kentucky - 09 Jul 1987
Frank Neaves 1846 Henry, Kentucky, United States - 1931
Edward W Neave 1902 Bracken, Kentucky, United States - 07 Oct 1965
But you can always look at the Neff Activity Feed and see who is working with that surname. You might gain more interest if you post the photograph.