My good friend and neighbour had a stroke 6 years ago but made a good recovery except that she gets confused by numbers. Of late she has started to become a bit incoherent at times.
A few days ago I asked her about her family history but she was dismissive and said he couldn't understand why anybody was interested in that sort of thing. I raised it again next day and suddenly names and dates came out in a torrent, with little hesitation.
Yes, talking about these things might help her to remember them longer. Just be careful she doesn't get frustrated by forgetting or getting confused. It needs to be very relaxed and non-confrontational.