My daughter was sharing apple ids with me


I set up family sharing and a new Apple Id for her, so now she's
itunes- (still shared with me)

But on her iPhone (no cellular) for iMessage and FaceTime she still has apple id, but is reached at both on an added address

But if i logout and change her appleid in message/facetime to her @icloud address, it won't let me add the @gmail address to be reached at. It won't send verification email and says error. But then if i change it back to the appleid, her gmail address is verified there.

Any advice? Im trying to rid her of the @yahoo address for everything other than iTunes, we are having iMessage cross receiving issues.