Reunion etiquette. That is the topic at the morning show that I am watching right now. The guest psychologist said that no one has really written about it but we should always apply the golden rule, do not do unto others what you do not want to be done unto you. Simply put it, be nice as you want others to be nice to you.
There are some sensitive questions that should be avoided:
1. job – other people are not that lucky ( though some are just lazy 
) to find a job.
2. weight – who could tell if someone really overate or his metabolism is just slow?
3. kids – I have a cousin who does not have a kid and I know it is painful for her
4. marriage- I also have a cousin who is still single at her 50s
For me, beauty is most attractive if that is your inner beauty that is radiating out!