Not sure when you're traveling, but if you are using the
free dining promotion you can simply age your daughter up to 10 years old and she would get the adult dining plan. It's only about $20 more for the increase in child to adult park admission. We did this for my son 2 trips ago when he was 9. However, If you're not doing free dining then it would of course be much more expensive to have her as an adult on the plan.