Family gathering

We are going to Anehiem, Ca in Sept for a 'Family Disney trip.'  I am going because I haven't seen my nephew in a very long time.   He's a Marine.  It's starting to look like I won't be spending much time with him.  I guess what I get is going to have to do.  Yes, I'm being a little selfish.  It's just that everyone else has seen since him much more recently.  Yeah, I know...........
My sisters oldest started planning this trip and her youngest took it over cuz we didn't want the oldest to be in charge.  She likes it too much!  It doesn't help that the oldest and I don't get along.  I think part of my issues are because I'm not making my own plans.  I really don't like it much at all.  Also, my money is tight and it's being tied up without my help.  I could put my foot down then I would be the party pooper.  I guess that wouldn't be the 1st time! 
I'm just frustrated.