If your sister is paying, go and enjoy it best you can! My last real vacation (over 10 years ago) was to Las Vegas for my twin brother and I's birthday weekend and he paid for almost everything. (I guess I kinda owe him a vacation sometime? but I never go anywhere - plenty of fantastic places to go for day trips all around here.)
Also, my vote would be for Portland. Because I've never been there & I hear they like to keep it weird. 
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No

for supporting trump. Because doing so is deplorable.