Years ago, I sent a letter to my sixth grade english teacher thanking her and telling her how I srtill remembered her lessons. I didn;t know it then, but she was retiring that year and they read my letter at her retirement dinner.
years after that I ran in to her at the grocery store. She had no idea who I was and seemed a bit confused. So sad. I was glad I wrote to her when she was healthy enough to appreciate the thanks.