Will the reunion be very happy?

I don't know. A reunion won't be fun. If we haven't seen each other for decades, the reunion is basically happy, because the feelings between classmates are pure, and everyone wants to know the changes and situations of classmates for decades. If you get together often, it depends on the feelings of these students. If you talk too much, you will feel bored, even bored and in a bad mood when you are with people with different values. It will be happier to be with like-minded people. Appropriate participation in different people's class reunion can absorb all kinds of information, and it is not bad to talk less and listen more.