I think you might be timing things too close together. If you start at 4:00, go for dinner around 5:30 or 6:00. That's usually when the most socializing goes on, and people have a lot to talk about in the beginning, and the kids go off and play together, etc. I'm going to one on Thursday and one on Friday and they both start at 3:00. I'm glad they are starting early, because I have a long trip home from both.
-Nancy