To help others help you, at least give us some time frames to go on.I almost didn't do any search on this line because of no time frames.The only reason I did, was because of the unusual name of Mordecai.
Defiance is a very short distance from Wood Co., OH.It would appear that both Mordecai and his wife Nancy died between 1860 and 1870 in Defiance Co., OH - Tiffin Twp.
1850 Defiance Co., OH - Tiffin Twp. - August 7, 1950 - page 46 623/623 Cameron, Mordecai 74 - no occ - PA Nancy 67 - MD S. L. (male) 30 - farmer - 600 - OH Lucretia 21 - OH
1860 Defiance Co., OH - Brunersburg P.O. - Tiffin Twp. - July 30, 1860 - page 138 964/952 Cameron, Jn 53 - farmer - 5000/797 - PA Lydia 49 - PA Simon 20 - PA William 17 - PA Robert 14 - PA John 9 - PA Olmstead, N. (male) 29 - PA
965/953 Cameron, M. 37 - farmer - 1500/1202 - PA Mary 30 - PA Ellen 4 - PA Mordecai 85 - MD Nancy 72 - MD
*************** From the LDS site:
Mordecai CAMERON Sex:M Birth:25 Dec 1775 , Lancaster, Pa Death:25 Feb 1863 , Defiance, Oh