It's my daughters 6th birthday party tomorrow and I sent out invitations in October knowing that people plan things at weekends especially with Christmas looming. I asked for RSVPs to come back by mid November as the party venue like to know numbers ASAP. I've just had a message from one of the invited kids mums saying she can come tomorrow. I can't make amendments to the booking or extra party bag goodies that late notice. I replied but she hasn't read the message. What do I do if she just turns up??