Hi Pinacoloda1,
I can tell you as a counselor, that's called putting someone in a double bind, very damaging to the psyche! My D attempts to do this all the time with my JJ (he is going to be 7 next month). I really abhor this behavior, it extremely confusing to children. For our situation I don't leave my D alone with JJ for more than an hour at a time, it's just too much or her. If I should hear her doing this to him I intervene immediately. I simply ask my D to think about re-phrasing the question or statement. Usually she can't do this, so I offer suggestions. By no means was this an easy compromise for us.

My D use to tell me to stop butting in, stop taking over her right as a parent, stop usurping her authority. It's taken 2 years for her to understand that this behavior is harmful. Any way I have had full guardianship of JJ since the first of this year, that was my D's choice, it has changed a lot. I do my best for JJ to understand that she IS HIS MOM, but I make the decisions.
I know this must be a painful thing for you to hear. How old are the kids?