My mum is the same and occasionally still does it.. if ds is throwing a tanty she will say in a cranky voice "ARE YOU THROWING A TANTRUM"? i usually just say, of course he is, he is 2 its the only way he knows to get his frustrations out! Mum used to say the same thing when he was younger too "your a naughty little boy, aren't you" and it used to p*ss me off big time. I eventually had to yell at my mum and tell her not to say those things to him and not to belittle him, as she wouldn't listen to me when i gently tried to push my point accross.

Set some ground rules: eg: she is not to call your dd naughty, you are to do the dicipline because you are the mother etc etc if she can't accept your way of parenting, tell her she will have to move out.

Sorry, its proably not the best advice but that is what I would do if my mother lived with me.