I wasn't really a fan before, but it has kinda grown on me and I think going w/ the mn on it is wise... though it could have
Millie as a nn if you wanted your DD to go by that. I like
Eliza Mildred better than
Lucy Mildred for multiple reasons:
1) flow is better
2) I just plain prefer
Eliza3)
Lucy seems a bit more popular now than it used to be and
Eliza's still less common
Mildred Kathleen sounds nice if you were to go by her mn.
Katelynn Mildred could also work if variations on
Katelynn weren't so overused.
I'm sure there are others that would work too, but
Eliza Mildred is pretty decent.