Looking for Parents of Cyntha Evans of Knox County KY

Cyntha (Syntha) Evans was born about 1812 in Knox County, Kentucky, and married a man from Pennsylvania named John Dean. They had a son in Kentucky, and called him George W Dean, in 1838. Then they moved to Huntingdon, Pennsylvania. She died in Blair County, Pennsylvania, in 1885.

I have searched Ancestry.com but have not found the names of her relatives, nor where they came from. Any help is appreciated.