If your grandchildren didn’t acknowledge you on that day, it’s probably because other things of greater importance were happening, like the commemoration of the events that occurred ten years ago.
However, if you are fortunate enough to have grandchildren, remember that they are growing up faster than you are growing old, and enjoy every moment that you can with them. You’ll live on in their memories long after your body is used up. Make the memories significant. Give them the best of who you are. It’s really the only legacy worth leaving.