AITA for declining to fly to Canada with my Mom for her birthday?

It's pretty simple. A less than a week ago, my Mom was taking pictures, and I ask for what, and she answers to update her passport. I don't think much of it when she says she wants to visit Canada, because she's flown out before.

Last night, I find out from my sister "Hey, you're going with us." I initially show hesitation, and later decline, but she said flat out, no, you're coming with us. Now I'm not heartless. I was already planning to take my Mom out somewhere nice for her Birthday, but flying out from the east coast to Vancouver, Canada isn't something I want to do, so I said no. Is that unreasonable of me?