So not kosher to tell your kids what to call you. However, it might be that in her eyes, they're not respecting you by putting a moniker after the yes or no. You are as respected as you feel, and whatever you are teaching your kids is right for your family. While I understand the stress of confronting your MIL about this, I think this is the message you have to convey to her. When DS was born, she insisted on calling him by his two initials, which I'll call DJ. I hated that, and I said, please don't call him that, he's either Daniel or Danny. Not DJ (not really his name, just giving commensurate example). She wasn't happy with me, and now refuses to call him the shortened version of the name that every single other person calls him, and will only call him the full name -- in protest. But it was that important to me that if shew wants to be annoyed all this time later fine. I hope you don't encounter that kind of resistance, but I would not let her tell your kids to call you ma'am if that's not what you want. And it sounds like you may ahve to directly tell her, hey please don't do that.
Good luck!
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