Ummm, sorry, but nobody is excusing the lame parent..... That is just not the point!!!!
Lame parents are out there...
And, even with parents who are not always lame "LIFE" happens...
IMHO, these days... unfortunately, one will NEVER be able to count 100% on RSVPs.
I can't see how anybody would even go by that assumption.
The point is that the OP is having a freaking coronary because of a kids birthday party.... It is just an unbelievable burden to her to maybe have planned to be prepared for all of the children whom were invited...
This was not an open (to the whole class) invitation...
This was a PERSONAL invitation.
The OP's daughter chose to invite Mary.
And, in this case, friendship and common courtesy should dictate that Mary is welcome to come to the party, RSVP or not.
Yes, this mother may be clueless.
The whole "can you pick her up and bring her home" is just totally and incredibly over the top...
However, we are not discussing this with that mother.
She is not here.
I will refrain from comment about this other mother.
I will say that, no matter how lame or clueless this other mother is... The OP and her daughter issued a personal invitation to 'Mary'.... And, there is no way that I would have been so quick to exclude this child.
Like everybody else has said.
It is a freaking child's birthday party.
Not a $10,000.00 wedding.
The OP is very obviously going to continue to give herself a coronary over this little party.
She is going to continue to justify the whole thing by pinning it on how bad this other mother must be...
But, really... I am like... look in the mirror.
I guess I'm looking at it from my perspective. I see my DD begging for a bowling party. I check into it and find out it's $50 per 5 people and realize that if I limit the guests to 9 we can afford it (including $$ for food, balloons and gift bags). It will be tight, but it will my DD so happy so we do it. All kids but 1 RSVP (not bad). In the mean time, I realize we have an extra spot and I have a friend who is going through a really rough and it would mean a lot to her and her DD to have an afteroon of fun. I know my DD will have fun with an extra girl (kids become best friends so quickly) so I invite her. Mary' mom didn't RSVP and I'm not psychic, how was I to know Mary wanted to come? I guess I see it as once RSVP dealine passes, the invitation has been declined.
I don't think the OP is having a coronay (I think some of us posters are reacting more), but I think she was just super frustrated and needed to vent. Who knows, this party may be stretching her budget as much as a $10,000 wedding, but she wants to make her DD happy.