No, that's not too young, as long as you're willing to work around her schedule. That shouldn't be too much of problem since you've been before. I wouldn't consider any age too young, provided it was a baby who was old enough to be in crowds without getting sick and it wasn't too hot. If you were planning on only going once, it might be good to wait a little while, but as long as you plan on going every few years or so, she'll have a blast every time. She may not remember most of it, but there will be pictures of her having a good time, and she'll enjoy looking at them.