Would anybody else be annoyed

Would anybody else be annoyed or am I overreacting? First, this is my moms first grandchild so of course I understand how excited she is but its like she's trying to take over. She already plans on taking the first few days off when he's born to help, which she never asked, just decided. While I'm sure we may need help occasionally I definitely DONT want her there constantly. And she gets offended about my fiancés mother watching him, as if she should get to watch him all the time, every time. (When honestly she's an alcoholic and I don't want him around her much anyways)