If the allergy is life-threatening it's almost impossible to eat out safely.
Even well-meaning waiters and chefs aren't necessarily going to be able
to give you accurate information.  They can tell you something doesn't
contain milk or butter, but will they know if something they are using has
whey or casein in it?

If it's not life-threatening, my strategy is to order a plain grilled steak
(or boiled lobster) and a plain baked potato.  Occaisionally you can get
plain steamed veggies.  A plain hamburger would probably be fine too if you
can get them to let you read the ingredients on the bun (or not eat it,
perhaps bring your own).  Salad with a vinaigrette dressing or oil and
vinegar is pretty safe too.  But I don't know if your daughter would find
this menu acceptable!  Most kid-friendly stuff is out.  Everywhere I've
asked all their breaded stuff has milk in the breading, for example.

Do you have Bertucci's where you live?  Someone had a fatal allergic reaction
there a few years ago, and they're very allergy aware now.  Their menu states
that they will be happy to share the ingredients of any of their menu items.
But it's a pizza place, so there's a pretty good opportunity for cross-
contamination!

Good luck!
--Robyn