My wife and I started developing motion sickness a few years ago. We found Sea Bands:
When we took our boys to Disney, we wore these all 8 days and had no problems.
Now, we did find out that we can't do spinning looping rides one after another. We went from Firehawk to Flight of Fear a couple of weeks ago and had some trouble. But, after figuring out what we can/can't do right after each other, we are good to go!
Hope this h