I could see a relative quietly asking if they could being a date.. The key word is ask and gracefully accept "no".
People's true colors show at times like that!
As for RSVP ... So many people really don't know what it means. I think it also depends on culture. One year I had a birthday party for my dd, she was 4 or 5. I had 10 RSVP....25 kids showed up. Horrible, I did not have treat bags or supplies! The next year I did not put my address on the invitation...so at least they had to call
Sibling and extended family is a problem at parties too! When the kids were little I would always call and ask if I could bring the sister and offer to pay if there was a per head charge, some people said no. I had a mother who brought two sisters upset with me because I did not have treat bags for them.
I didn't know they were coming.
In Miami everyone is late. It is a joke thAt you have two invitations printed...one with Miami time the other American time..lol
I think it is rude tobe more than 10 mins late
As for showers, It is poor etiquette to throw your own party or even a close family member. I see nothing wrong with a showere for each baby, but the mom should Not be surprised with lower attendance ...
What I HATE is charging for a shower and expecting a gift!!!