There is a lot of great info available on this forum, for helping you child become a better hitter. Its helped tremendously with my 9yr old. That being said, I would try and perform any advice someone gives you yourself. As well as watch the pros if that's what they are doing. That way you can relay that information better to your DD.
YES! Feel it for yourself.
Hansen Principle - "Always compare what anyone says about the swing to slow-motion video of what the best actually do."