There is certainly a strong possibility that the LDS database is incorrect regarding Eliza Black as being in the lineage of Adam Black/Elizabeth Green Cockburn via James M. Black/Jane Sharp, etc.Such an error would not be unusual.I can certainly answer one of your concerns.There was an Eliza A. Black (b. ~1810-1812 in West Virginia) who married Sylvester McCown in Kanawha County, West Virginia in 1843.Sylvester McCown was born on 24 November 1804 in Kanawha County and died in Irontown, Lawrence County, Ohio.Eliza and Sylvester migrated to Lawrence County, Ohio, following their marriage in West Virginia.It also appears that this Eliza Black was Sylvester's second marriage as he was married to Harriet Summers (b. ~1810) on 29 May 1831 in Kanawha County.This Eliza Black could well be the daughter of Adam Black and Elizabeth Green Cockburn.Some records show that Adam and Elizabeth Black also had a daughter Elizabeth in addition to Eliza.This Elizabeth could have been the wife of Martin Van Buren Snodreass, Jr. and later the wife of Carey Toney (He married Eliza Ann Black Snodgrass very late in life, i.e, 10 January 1892.I believe that the Eliza/Elizabeth Black who married Martin Snodgrass, Jr. was born on 26 January 1826 in Greenbrier County, Virginia/West Virginia.It appears that the father of Adam Black is likely Abraham Black (b. ~1760 in either Scotland or Virginia) rather than James M. Black.In addition, there seems to be inconsistancy in the names and birth dates of the children of Adam and Elizabeth Black.Your might look into the possibility that Adam Black had a daughter Eliza and another daughter with the given name Elizabeth.I see very few other possibilities as the Eliza/Elizabeth who married Martin Snodgrass, Jr., had a number of children by this marriage during the same time frame that the Eliza Black who married Sylvester McCown is also having children from that marriage.Interesting dilemma.Let me know when you find a solution.