Hi Avril,
I've just found Euphemia on the IGI, though I suspect he birth date there is incorrect.
I entered just her parents and she came up at the bottom of the list.
It has her as born ABOUT 1852, but her parents didn't marry utnil 1856, and at present, I have their first child, Elizabeth Richardson Smith, as born 1858, so I would suspect that her d.o.b. might well be 1856 or 57, and not 52. Or a younger child with an even later date. I have no idea why they wrote 'about 1852'.
Sorry, also forgot to tell you that I'm descended from Cornelius and Katherine's son, Robert, who is my GG grandfather. He married Sarah Eliza Penniston in 1863, and there is more to twll.
Brian