Christmas gift for Sister in law?

I have a 37 year old sister in law who is quite finicky.We draw names and I picked her. She has a sister who works at a spa, so I don't think I can buy a gift certificate for a pedicure etc. I don't want to give her a food basket, maybe a gc to a restaurant. Does anyone have any other ideas? I'm looking to spend between 30-40$
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Does she have any hobbies or interests you know of? I gave magazine subscriptions one year and my family not only loved how I'd matched them up with their interests, but they thought how nice it was every time a magazine came in. Year round benefits! As for restaurant gc's. I would go with a middle/high end type like, Olive Garden, Red Lobster, or Outback. $30-40 can be a nice meal for two at any of those places.
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