We have invited one family, and I can't get an answer out of the mom as to whether they're coming or not. My wedding is in one week, and I've asked her twice for an answer already. At first she told me she'd let me know, which was fine when it was about a month out, so I let it go, even though it was past the RSVP date. The second time, she told me she had to check with her kids' dad, and she'd let me know after her son got his baseball schedule. Well, my son, who plays in the same league, got his schedule last Tuesday. I still haven't heard from her, and really don't feel like contacting her a third time to ask if she's coming.
At this point, I'm apt to just leave them off the list. Fortunately, I hadn't included them in my final count, and another friend of mine witha family just found out she's having surgery on Friday, so they had to cancel at the last minute, so there's room for this non-responding family.
But this is really rude, IMO. I mean, a party of 4 is significant when you only have 50 people at your wedding. (Not to mention the $300 + she's leaving me in limbo!) Plus, she's messing with my seating chart!