Have you eliminated or confirmed Ephraim H. TURK (1791-1870) and Maria MOORE (1803-1877) as the parents of your great-grandfather Robert TURK (1832-1892)? If confirmed, I would be pleased to share what I have on this line with you.
You mention that you can get some exact dates on the children of Claude TURK and Flossie DRAKE. I would appreciate being able to piece some of the Venango Co., PA, TURKs together. For example was the Chester in this family born 24 Jul 1906? As much TURK-surname related information as you care to share will be appreciated. To the extent that it merges into our greater database I will be happy to send you what I have. I have 44 TURK-surname related entries from Venango County and 98 TURK-surname related entries from Butler County, which appear to be in addition to the TURKs referenced in your postings.