I'm with you as well.

Parents of a little girl, love kids...but have a very firm "no children allowed" rule. Think it is hard to do at a party...we did it on our wedding as well. Had several people try to guilt trip us into bringing their kids...but gave firm, "Sorry, we look forward to seeing you at another event soon."

Your party...your rules. Real friends understand...and it is more than fair in my book!