I don't think there is a set age, I think it depends on the child. And it also depends on your touring style. If you want to stay in the parks all day, and your child would be cranky without a stroller, then I'd use a stroller. If you are the family who takes a lot of breaks, you might not need a stroller.
Dreams Unlimited Travel is committed to providing you with the very best vacation planning experience possible. Our Vacation Planners are experts and will share their honest advice to help you have a magical vacation.