Will my grandmother remember having a flashback to an old memory?

tonight we had an issue with my grandmother. it started out that we were told my sister and i were telling people about something that never happened, (it was not a good thing). so we talked to my uncle who lives next door to my grandparents, trying to figure out "who" was telling my grandparents that we were saying these bad things. finally he called saying that apparently she had a flash back from years ago with a conflict with my mother, but she thought my sister and i were going around telling people about it when we weren't. my question is now that we have figured out that it was a flashback she had and not someone telling her that we were saying these things, will she remember having the flashback? because it was such a bad memory we are worried it will bring her grudge back to my mom. will she forget about the flashback all together?