I have a photo of the gravestone, found online. The inscription is obscured by lichen, but would be clear enough to read with some careful cleaning. I have no doubt the transcription is correct - you can read bits of it in the photo. Elizabeth surely was born in 1634 or 1635, if the gravestone is correct. She was in her 91st year, meaning she was 90. The date on the stone isn't double-dated to account for the Julian/Gregorian calendar difference, so without other evidence (I haven't seen any), it can't be said if she died in 1725 or 1726. When there isn't a double date, it's more likely the Julian date is meant, so in this case 1725. Given that she died on 7 January, she would very likely have turned 91 in either of those years, making her most likely born in 1634, but possibly 1635.