I just got back from Disney on Monday. We took our 4yo DD and our 8 month old dd as well. We took our 8 mo old on every ride that did not have a height restriction and every show including it's tough to be a bug (which can be very frightening). She ENJOYED every second of her experience. We did many character breakfasts and dinners and she just loved every character. She wasn't afraid in the least bit and she even let them hold her for pictures. The only time we did the child swap was for Space Mt, TOT, ROR etc.
We all ahd a blast and I would do it again in a N.Y. minute LOL!!!!