Late stage question - French delusions?

@Andr3a - I had a similar experience. It is very strange and not a lot to explain it.
I came in one day, to her care home, and out of the blue, after not having spoken anything but English for at least forty years, she said" Ou est les enfants?" I was a bit stumped. She did used to speak french and my sister and her family live outisde paris, so it isn't totally outisde experience, but still odd.
I tried replying in my very bad french, but she was very confused. It never happened again. I think this sort of regression or just verbalising things they hear or remember (Mummy used to shout "Margaret" regularly, for no good reason), and you may never know why, or exactly what they are on about.
Towards the end, I don't think Mummy knew who I was, but she seemed glad to see me. I think at that point, that was enough.