Engagement Party Stress!

My engagement party is this weekend and I'm getting a little stressed! Of course there is probably nothing to stress about, but it runs in the family! The party is just for our parents and our bridal party because our parents have never met and most of our friends don't know each other, so we thought it would be a good idea to get everyone together! I just hope our parents all get along (we both have 2 sets of parents so it could be tricky!) and I hope everyone has a good time. Several people are coming from out of town so I want everyone to have fun so they don't feel that it was a wasted trip! I know, I need to chill out. I will let you know how it goes...