We have shared information before in the past. I am still not quite sure who Polly's parents are, but this is my best guess.
Descendants of Joseph Lock
1 Joseph Lock d: Aft. 1800 in Barren County , Kentucky . +Kesiah Harvey m: February 23, 1792 in Madison County , Kentucky ...... 2 Polly Lock ...... 2 Jenney Ann Lock .......... +Bazil Shaw m: May 27, 1846 in Barren County, Kentucky ...... 2 Betsey Lock
Joseph Lock is the brother of my Rev. Jacob Lock. Your Hardin B. Walters was living in McCracken County Ky in 1850 as was George F. Lock, Jacob's son. The age of Polly Lock daughter of Joseph Lock, has to be fairly close to the age of your Polly Lock. While I can't prove it, I suspect they are one and the same Polly Lock.
Little is known about Joseph Lock's family, and few records have been found. If he had any son's, we do not know about them yet.
Wish I could have been of more help, we just don't know much about that side of the family.