Car Sickness

Any advice welcome! my 21/2 year old has recently been quite violently sick in the car a few times and is now completely car phobic not even wanting to go on short journeys. Not really sure how to deal with this so have just been telling her she wont be sick she will be fine. Her phobia seems to be getting worse so wondering if I should approach this in a different way and talk to her more about it. It mill become an issue in the future as we have family and friends that we regularly visit up to 2 hours away and have a holiday in dorset in August! I know the methods of trying to prevent sickness; the bands dont work as she wont keep them on, tried singing etc just seems to make it worse, even got a portable DVD player to try to distract her. As I said at the beginning, any advice welcome!!!!!!