Response from the ancestry tree owner - SaraK on McGill:
SaraJK19 Today 7:48 AM GMT Hi Kate,
I am related to the Pistners (Charles' wife, Rose Pistner), so I don't know much about the McGill's. But I think you are right on with your information. I am very impressed with all your research and information!! I do think John M is probably the brother of Charles McGill, and I agree that the best thing for Carolyn to do would be to obtain John's death certificate or to obtain church records from Cincinnati.
You really seem to know a lot about genealogy resources, and I think you have provided some very helpful information! Trying to track down info on some ancestors can be very difficult, especially when you live in another state! However, it does seem you can find more and more records on internet sites such as Ancestry.
I live in California, but most of my family came from Illinois and the Cincinnati area. I am planning to go to a genealogy conference this summer in Illinois, and I am hoping to make it to Cincinnati also, to do some research.
I wish I had more info about the McGill's, but you have been very helpful with all of your research and resouces. Carolyn should be able to find out more about her family soon!