If you want a stroller for her because you think it would improve your trip, do it, and don't let anyone else tell you that its not right. For My son, I used his maclaren volo stroller until he literally wouldn't fit, just for Disney. He walked starting at 9. Now on the other hand, DD is 6, and she walked the entire 10 days, and we took a stroller, but didn't need it. People will give their opinions, but you are spending a lot of money, and if it will make your trip better, do whatever it takes. A friend of mine rented one when her DD was 7, but she was big for her age. She fit, crammed in a little, bit it did the trick