Ensure that those that did RSVP have one. If you run out of food, the kids won't care. But when the other parents come in, say..."Oh, I didn't know you were coming." And the more that trickle in, "I hope I have enough. I only got a (x) RSVP's."
Personally, I don't know how someone can't take 60 seconds out of there day to shoot an email, text or pick up the phone to RSVP to an event because it CLEARLY makes it so much easier for the host/hostess! And don't give me that, "I don't have time." Because how much time does it take to prepare for a party.
@AV: I can't believe that people actually can't figure out RSVP to xxx-xxx-xxxx or (insert email addy here). I think those people are just inconsiderate. They are likely the one's that drop off late and pick up late too.
But in the future, A., you could simply put "Regrets only." to accommodate the busy lives of your guests.
Hope you and your daughter have a wonderful 3rd birthday. It will be fun...so have a good time! And take pictures!
And I am very busy, like everyone else. I'm also organizationally-challenged so I stick that invite where I will see it, and tape it on a cabinet in front of my face, if I have to, so I don't forget. Why? Because if there is an RSVP, that means the hostess wants to know if a guest will be coming. Manners: It's about making others feel valued and appreciated. Always.