I just woke up suddenly from my dream, because I dreamed of my grandfather, who died 12 years ago. I was not at home when he died, and the communication was not so good at that time. ...

Personally, it's because you haven't seen him for a long time. You should go back with Qingming on the anniversary. I just heard a similar story from my friend today. At first, he dreamed of it, but later, he would go back to burn it for grandpa every year. It may be inconvenient, but you have to go once every two or three years. And I have the opportunity to provide photos of my family. If you can't go back, just say goodbye, talk and put some delicious food on holidays.