If you decide to be generous and let her in, be very careful. She may very well want to get to your wife and the baby with "the truth." She'll have all day to subtly preach and get an in with the baby. My mother didn't want to visit with me but wanted to take my young children for the summer. I knew all too well they'd be brainwashed and had to say no.
Please let us know how this works out.
Emma