Finding out baby's gender

I have my anatomy scan next week. Thing is my husband won't be able to make it but someone will either have to watch our 9 month old or go with me and keep her occupied. Everyone knows I do not want to find out the gender until birth. We have 5 kids already. Our oldest is a boy and then 4 girls so I rather find out baby's gender at birth. My Mil want to go and keeps saying the tech can just tell her and she wont say anything. She can not accept that she is gonna have to wait like everyone else. I dont even want the gender in my chart just in case the dr slips and mentions it. I'm almost ready to just reschedule my anatomy scan so she doesn't have to be the one go with me. Should I just let her find out or make her wait too?

It's okay for baby to come. If the entire family wants to be present, they allow it.