where was my great grandmother born?

If you have LOTS of time on your hands, you might have luck on the US genweb archives for PA :

Code:

http://www.usgwarchives.net/pa/pafiles.htm

There is a site-wide search engine. If you only search "Johnston" there are thousands of hits, but there is probably a way to narrow that some. Unfortunately, I've got too much going on to sit down and look.

Were they Catholic? Again, I wish I had the time to do it, but there might be a way to find some parish records - but that's just a guess.

Sorry not more help.

 

Another site which may help.

Code:

https://www.amyjohnsoncrow.com/8-sources-to-fill-the-1890-census-gap/