I am arranging a seating plan for a family reunion. There are 25 people for nine meals.?

Why don't you just tell them to sit with different people for each meal, so what if they sat by that same one at the most two people!

Why don't you stop trying to be so scientific about it and just instruct everyone to please "mix it up" and sit with different groups at each meal? I mean good grief, lighten up and don't be so controlling, you and everyone else will enjoy the reunion better.

Here is an easy idea without too much hassle, it may not make everyone share a table with everyone but see what happens. Assign every seat a number. Number chips 1-25 and put in a bag. Before every meal each person draws a chip and that is where they sit. 1 more idea - basic musical chairs - seating chart for one meal - next meal one or two people move to the right, next meal, same thing, etc.

Wow! Sounds like you put a lot of thought into the seating 'charts'. My thought is that family reunions are for re-uniting the family. Catching up, like one of the other answerers said, is the point. So less formal is the way to go if it were my family. I too would like to start a reunion tradition for my family but it is just the 5 siblings and their kids. This year would be our first and so it should be kept simple - maybe some planning for future years would be a good idea for one of the activities. I'll read back later in these answers - maybe someone could give me some ideas for activities during a week so we can get started. I envy you - I think family is so important so no matter how you do it, do it and enjoy.

Are you really sure you want to do the seating that way? A lot of people will resent it and some will be uncomfortable if forced to sit with people they don't know well. The plan may not have the desired effect and could kill the energy of the gathering. As a compromise, what about letting people sit where they want, but then playing a round of musical chairs for the dessert course?