I haven't heard this either but there is a sticky at the top of the page that might have some info (I think MaryKate is the thread starter). I do know Vitamin D is fat soluble, so you *can* get too much. Also a little bit of sun exposure, which almost everyone gets anyways, unless you are particularly dark skinned and walk around particularly covered up, is enough to get you what you need.
I love your little girl's name
