I say go, unless you really feel the need to spend that time with your sis. I only get to see my sis a couple of times a year now, but when she comes down, she does her thing and I do mine and then we meet up and do our thing. Just let her know you have plans and maybe have her meet up with you at the end of the tour and go to lunch or something. I'm sure she'll understand. And besides, if she is moving there, you'll see eachother a lot.