I found one unsourced entry listing her place of birth as Staffordshire. That may have simply been a guess. I am curious about the Staffordshire Jervis connection to Wistaston. I trace my own line back to James Jervis, b. Wistaston in 1742 and I am stumped as far as going back any further. The Wistaston line may be old; an Ellyn Gervise was born there in 1626 to father Robert and then there is no more Jervis activity save for Eleanor until about 1738. I use the LDS Record Search Pilot which brings up different data than its regular Family Search vehicle. For some reason, it is finicky about Wistaston, sometimes yield few or no results. I contacted LDS and this will not be a permanent search tool unfortunately so they have no plans to fix it. If you don't get results using it, try Jerviss. It is supposed to use Soundex but Wistaston appears to be the exception.
Bill Jervis